diff --git a/automatic_updates_extensions/tests/src/Build/ModuleUpdateTest.php b/automatic_updates_extensions/tests/src/Build/ModuleUpdateTest.php
index 1275c177805318ede016d0a2e91bcae5cd7c345d..f0c8425f05bfbac46bf45bdd5ba40fd9b97cfb5b 100644
--- a/automatic_updates_extensions/tests/src/Build/ModuleUpdateTest.php
+++ b/automatic_updates_extensions/tests/src/Build/ModuleUpdateTest.php
@@ -10,6 +10,7 @@ use Symfony\Component\Filesystem\Filesystem as SymfonyFilesystem;
  * Tests updating modules in a staging area.
  *
  * @group automatic_updates_extensions
+ * @internal
  */
 class ModuleUpdateTest extends UpdateTestBase {
 
diff --git a/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php b/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php
index 41701d8ae3b43227e88c59d27f6bb2c8bad9eb24..f6966cc691406d14a16b1651b7722e05bc75366c 100644
--- a/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php
+++ b/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php
@@ -20,6 +20,7 @@ use Drupal\Tests\package_manager\Traits\PackageManagerBypassTestTrait;
  * Tests updating using the form.
  *
  * @group automatic_updates_extensions
+ * @internal
  */
 class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/automatic_updates_extensions/tests/src/Kernel/AutomaticUpdatesExtensionsKernelTestBase.php b/automatic_updates_extensions/tests/src/Kernel/AutomaticUpdatesExtensionsKernelTestBase.php
index b6bd8caf029e7db26acdac133e2087421d90d754..a812dd174ef38c41a6fdc2260f4e8c791ae56c69 100644
--- a/automatic_updates_extensions/tests/src/Kernel/AutomaticUpdatesExtensionsKernelTestBase.php
+++ b/automatic_updates_extensions/tests/src/Kernel/AutomaticUpdatesExtensionsKernelTestBase.php
@@ -13,6 +13,8 @@ use Drupal\Tests\package_manager\Kernel\TestStageTrait;
 
 /**
  * Base class for kernel tests of the Automatic Updates Extensions module.
+ *
+ * @internal
  */
 abstract class AutomaticUpdatesExtensionsKernelTestBase extends AutomaticUpdatesKernelTestBase {
 
diff --git a/automatic_updates_extensions/tests/src/Kernel/ExtensionUpdaterTest.php b/automatic_updates_extensions/tests/src/Kernel/ExtensionUpdaterTest.php
index 08a7a6f5f2b3feaa2d1c454d968eb3f345213e3f..c23333401da8492b8afd36e8d5b2a3a5145e993c 100644
--- a/automatic_updates_extensions/tests/src/Kernel/ExtensionUpdaterTest.php
+++ b/automatic_updates_extensions/tests/src/Kernel/ExtensionUpdaterTest.php
@@ -12,8 +12,8 @@ use Drupal\Tests\user\Traits\UserCreationTrait;
 
 /**
  * @coversDefaultClass \Drupal\automatic_updates_extensions\ExtensionUpdater
- *
  * @group automatic_updates_extensions
+ * @internal
  */
 class ExtensionUpdaterTest extends AutomaticUpdatesExtensionsKernelTestBase {
 
diff --git a/automatic_updates_extensions/tests/src/Kernel/Validator/UpdateReleaseValidatorTest.php b/automatic_updates_extensions/tests/src/Kernel/Validator/UpdateReleaseValidatorTest.php
index 946ce982602c15a95d9802de12ff8e5661268c5c..80a3103093725bad91cc2542937a9c54d554f4be 100644
--- a/automatic_updates_extensions/tests/src/Kernel/Validator/UpdateReleaseValidatorTest.php
+++ b/automatic_updates_extensions/tests/src/Kernel/Validator/UpdateReleaseValidatorTest.php
@@ -9,8 +9,8 @@ use Drupal\Tests\automatic_updates_extensions\Kernel\AutomaticUpdatesExtensionsK
 
 /**
  * @coversDefaultClass \Drupal\automatic_updates_extensions\Validator\UpdateReleaseValidator
- *
  * @group automatic_updates_extensions
+ * @internal
  */
 class UpdateReleaseValidatorTest extends AutomaticUpdatesExtensionsKernelTestBase {
 
diff --git a/automatic_updates_extensions/tests/src/Traits/FormTestTrait.php b/automatic_updates_extensions/tests/src/Traits/FormTestTrait.php
index 687823879e2e355a3730b2574533d8502a285d0f..e2451d81728d01e0442b48ec9e408f983e4d7b23 100644
--- a/automatic_updates_extensions/tests/src/Traits/FormTestTrait.php
+++ b/automatic_updates_extensions/tests/src/Traits/FormTestTrait.php
@@ -8,6 +8,8 @@ use Behat\Mink\WebAssert;
 
 /**
  * Common methods for testing the update form.
+ *
+ * @internal
  */
 trait FormTestTrait {
 
diff --git a/package_manager/tests/src/Build/PackageInstallTest.php b/package_manager/tests/src/Build/PackageInstallTest.php
index 46b2c6289289a3d63ac0a8b3d918f12271674c26..aa2167d32dd9a8c20263a6706959d2e110610634 100644
--- a/package_manager/tests/src/Build/PackageInstallTest.php
+++ b/package_manager/tests/src/Build/PackageInstallTest.php
@@ -6,6 +6,7 @@ namespace Drupal\Tests\package_manager\Build;
  * Tests installing packages in a staging area.
  *
  * @group package_manager
+ * @internal
  */
 class PackageInstallTest extends TemplateProjectTestBase {
 
diff --git a/package_manager/tests/src/Build/PackageUpdateTest.php b/package_manager/tests/src/Build/PackageUpdateTest.php
index 6427cc943a6ed83b661939f853885f3adea8bd2d..1547b238334f98b6c0d84abf47fd9d767386a3f9 100644
--- a/package_manager/tests/src/Build/PackageUpdateTest.php
+++ b/package_manager/tests/src/Build/PackageUpdateTest.php
@@ -6,6 +6,7 @@ namespace Drupal\Tests\package_manager\Build;
  * Tests updating packages in a staging area.
  *
  * @group package_manager
+ * @internal
  */
 class PackageUpdateTest extends TemplateProjectTestBase {
 
diff --git a/package_manager/tests/src/Build/TemplateProjectTestBase.php b/package_manager/tests/src/Build/TemplateProjectTestBase.php
index 14eb4387f813b3b12370501f078feab151d81472..f657bc276bc4439572732b9148b7097885cf165e 100644
--- a/package_manager/tests/src/Build/TemplateProjectTestBase.php
+++ b/package_manager/tests/src/Build/TemplateProjectTestBase.php
@@ -16,6 +16,8 @@ use Drupal\Tests\RandomGeneratorTrait;
  * (drupal/recommended-project or drupal/legacy-project) and contain complete
  * copies of Drupal core and all installed dependencies, completely independent
  * of the currently running code base.
+ *
+ * @internal
  */
 abstract class TemplateProjectTestBase extends QuickStartTestBase {
 
diff --git a/package_manager/tests/src/Functional/FailureMarkerRequirementTest.php b/package_manager/tests/src/Functional/FailureMarkerRequirementTest.php
index 97b726a3d72c6c72604a06b0d146915753d186e7..9da316ec671772b39b46cb4b9df1ca9a390ab2ce 100644
--- a/package_manager/tests/src/Functional/FailureMarkerRequirementTest.php
+++ b/package_manager/tests/src/Functional/FailureMarkerRequirementTest.php
@@ -10,6 +10,7 @@ use Drupal\Tests\BrowserTestBase;
  * Tests that Package Manager's requirements check for the failure marker.
  *
  * @group package_manager
+ * @internal
  */
 class FailureMarkerRequirementTest extends BrowserTestBase {
   use StringTranslationTrait;
diff --git a/package_manager/tests/src/Kernel/ComposerExecutableValidatorTest.php b/package_manager/tests/src/Kernel/ComposerExecutableValidatorTest.php
index d32e355b4fed790abe134e4a2eb958865b99cabc..7e5a90ed6d5292a450ec7a5c6a46630b0ff30e95 100644
--- a/package_manager/tests/src/Kernel/ComposerExecutableValidatorTest.php
+++ b/package_manager/tests/src/Kernel/ComposerExecutableValidatorTest.php
@@ -12,8 +12,8 @@ use PHPUnit\Framework\Assert;
 
 /**
  * @covers \Drupal\package_manager\Validator\ComposerExecutableValidator
- *
  * @group package_manager
+ * @internal
  */
 class ComposerExecutableValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php b/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php
index 389000e23f0e4e23b9b0781efd16528d21fd9b58..142b716c42ee3308acf55df97f99e7cc21b91530 100644
--- a/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php
+++ b/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php
@@ -8,8 +8,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\ComposerPatchesValidator
- *
  * @group package_manager
+ * @internal
  */
 class ComposerPatchesValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/ComposerSettingsValidatorTest.php b/package_manager/tests/src/Kernel/ComposerSettingsValidatorTest.php
index a2b60d2d32aaaa01dc44965e8a3abc9637fa7448..0ba92940de87ac6957db349348e0f6a37100f971 100644
--- a/package_manager/tests/src/Kernel/ComposerSettingsValidatorTest.php
+++ b/package_manager/tests/src/Kernel/ComposerSettingsValidatorTest.php
@@ -8,8 +8,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\ComposerSettingsValidator
- *
  * @group package_manager
+ * @internal
  */
 class ComposerSettingsValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/ComposerUtilityTest.php b/package_manager/tests/src/Kernel/ComposerUtilityTest.php
index b60bcc3cd626be3e2884102cb724f626b98714e9..210eafd8a1698d7528e6624cc81294c6baa05b50 100644
--- a/package_manager/tests/src/Kernel/ComposerUtilityTest.php
+++ b/package_manager/tests/src/Kernel/ComposerUtilityTest.php
@@ -9,8 +9,8 @@ use org\bovigo\vfs\vfsStream;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\ComposerUtility
- *
  * @group package_manager
+ * @internal
  */
 class ComposerUtilityTest extends KernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/CorePackageManifestTest.php b/package_manager/tests/src/Kernel/CorePackageManifestTest.php
index f6b8e4ed299ccc57e456266fb64c21b03f56d1bf..ce501f2815f99297fdd10517c5c14fd42119017f 100644
--- a/package_manager/tests/src/Kernel/CorePackageManifestTest.php
+++ b/package_manager/tests/src/Kernel/CorePackageManifestTest.php
@@ -20,6 +20,7 @@ use Symfony\Component\Finder\Finder;
  *   in the Drupal\Tests\Composer namespace.
  *
  * @group package_manager
+ * @internal
  */
 class CorePackageManifestTest extends KernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/DiskSpaceValidatorTest.php b/package_manager/tests/src/Kernel/DiskSpaceValidatorTest.php
index 6392fa585767af3ab0dcb7807fb8587fae99fc31..523b2d53df5bcbae1d92b73f1c18b7bbf18fb3fa 100644
--- a/package_manager/tests/src/Kernel/DiskSpaceValidatorTest.php
+++ b/package_manager/tests/src/Kernel/DiskSpaceValidatorTest.php
@@ -8,8 +8,8 @@ use Drupal\Component\Utility\Bytes;
 
 /**
  * @covers \Drupal\package_manager\Validator\DiskSpaceValidator
- *
  * @group package_manager
+ * @internal
  */
 class DiskSpaceValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/DuplicateInfoFileValidatorTest.php b/package_manager/tests/src/Kernel/DuplicateInfoFileValidatorTest.php
index b8d9a743c5015ad3739e6c47e5ef015b82b9d531..15eddc5be3f09e012461112a7205abb410abb3ca 100644
--- a/package_manager/tests/src/Kernel/DuplicateInfoFileValidatorTest.php
+++ b/package_manager/tests/src/Kernel/DuplicateInfoFileValidatorTest.php
@@ -8,8 +8,8 @@ use Symfony\Component\Filesystem\Filesystem;
 
 /**
  * @covers \Drupal\package_manager\Validator\DuplicateInfoFileValidator
- *
  * @group package_manager
+ * @internal
  */
 class DuplicateInfoFileValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php b/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
index 450c0fb7fe56b3753b3e1d3ee4173ac33f80e1b6..9ad3aecf5aaaa2e1c21e74a037226438547ee2be 100644
--- a/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
+++ b/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
@@ -10,8 +10,8 @@ use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
 /**
  * @covers \Drupal\package_manager\Validator\EnvironmentSupportValidator
- *
  * @group package_manager
+ * @internal
  */
 class EnvironmentSupportValidatorTest extends PackageManagerKernelTestBase implements EventSubscriberInterface {
 
diff --git a/package_manager/tests/src/Kernel/ExecutableFinderTest.php b/package_manager/tests/src/Kernel/ExecutableFinderTest.php
index c8da1b68dff9a21b7dd8fa7382653fcf5f80424a..82b92afc68debfe8ba6f9bb01945bcb9f11f316d 100644
--- a/package_manager/tests/src/Kernel/ExecutableFinderTest.php
+++ b/package_manager/tests/src/Kernel/ExecutableFinderTest.php
@@ -9,8 +9,8 @@ use Symfony\Component\Process\ExecutableFinder as SymfonyExecutableFinder;
 
 /**
  * @covers \Drupal\package_manager\ExecutableFinder
- *
  * @group package_manager
+ * @internal
  */
 class ExecutableFinderTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/FailureMarkerTest.php b/package_manager/tests/src/Kernel/FailureMarkerTest.php
index 37bc4bd24db0eb17aec58aa444119e6aba29ec6d..e00345c6c4b96b260e5e9cae06dad54066dbcd93 100644
--- a/package_manager/tests/src/Kernel/FailureMarkerTest.php
+++ b/package_manager/tests/src/Kernel/FailureMarkerTest.php
@@ -7,8 +7,8 @@ use Drupal\package_manager\Exception\ApplyFailedException;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\FailureMarker
- *
  * @group package_manager
+ * @internal
  */
 class FailureMarkerTest extends PackageManagerKernelTestBase {
   use StringTranslationTrait;
diff --git a/package_manager/tests/src/Kernel/FakeSiteFixtureTest.php b/package_manager/tests/src/Kernel/FakeSiteFixtureTest.php
index 88ee622c4de01f5cb68ce026b06f7f55d271cc6f..af8facb645bce50303e4fac57766a979107bbd0c 100644
--- a/package_manager/tests/src/Kernel/FakeSiteFixtureTest.php
+++ b/package_manager/tests/src/Kernel/FakeSiteFixtureTest.php
@@ -8,6 +8,7 @@ use Drupal\package_manager\ComposerUtility;
  * Test that the 'fake-site' fixture is a valid starting point.
  *
  * @group package_manager
+ * @internal
  */
 class FakeSiteFixtureTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/FileSyncerFactoryTest.php b/package_manager/tests/src/Kernel/FileSyncerFactoryTest.php
index 56aefbc94bbd3825e4e434237e00b27e12124934..e851c81cb5df6609da6562fb3a9e302a74d531d1 100644
--- a/package_manager/tests/src/Kernel/FileSyncerFactoryTest.php
+++ b/package_manager/tests/src/Kernel/FileSyncerFactoryTest.php
@@ -9,8 +9,8 @@ use PhpTuf\ComposerStager\Infrastructure\Service\FileSyncer\RsyncFileSyncer;
 
 /**
  * @covers \Drupal\package_manager\FileSyncerFactory
- *
  * @group package_manager
+ * @internal
  */
 class FileSyncerFactoryTest extends KernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/FixtureUtilityTraitTest.php b/package_manager/tests/src/Kernel/FixtureUtilityTraitTest.php
index 7b1ff0f0bfef623d68e12126cacf2dccb301d9ac..e95037eef0e725bda2df8cec0e8976cbc6e450e7 100644
--- a/package_manager/tests/src/Kernel/FixtureUtilityTraitTest.php
+++ b/package_manager/tests/src/Kernel/FixtureUtilityTraitTest.php
@@ -8,8 +8,8 @@ use Symfony\Component\Filesystem\Filesystem;
 
 /**
  * @coversDefaultClass \Drupal\Tests\package_manager\Traits\FixtureUtilityTrait
- *
  * @group package_manager
+ * @internal
  */
 class FixtureUtilityTraitTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/LockFileValidatorTest.php b/package_manager/tests/src/Kernel/LockFileValidatorTest.php
index f8f47244448fdfbdf6b18abefa96f4d83cef8d43..f4ff94bb13f23e4e2025861d80df9f80bad9cd30 100644
--- a/package_manager/tests/src/Kernel/LockFileValidatorTest.php
+++ b/package_manager/tests/src/Kernel/LockFileValidatorTest.php
@@ -11,8 +11,8 @@ use Drupal\package_manager_bypass\Stager;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\Validator\LockFileValidator
- *
  * @group package_manager
+ * @internal
  */
 class LockFileValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/MultisiteValidatorTest.php b/package_manager/tests/src/Kernel/MultisiteValidatorTest.php
index f8f8763d78a1d68508346b6aab67004ca605075e..5573fc7e15c553e13f0ab64090be6ba41c8732dc 100644
--- a/package_manager/tests/src/Kernel/MultisiteValidatorTest.php
+++ b/package_manager/tests/src/Kernel/MultisiteValidatorTest.php
@@ -7,8 +7,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\MultisiteValidator
- *
  * @group package_manager
+ * @internal
  */
 class MultisiteValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php b/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
index 39dc274cfbf1873efa1d863cf7ffd118c56be6a0..fa92f9410d16e944311611c24fb1d31c8fca4104 100644
--- a/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
+++ b/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\package_manager\Traits\FixtureUtilityTrait;
 
 /**
  * @covers \Drupal\package_manager\Validator\OverwriteExistingPackagesValidator
- *
  * @group package_manager
+ * @internal
  */
 class OverwriteExistingPackagesValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PackageManagerKernelTestBase.php b/package_manager/tests/src/Kernel/PackageManagerKernelTestBase.php
index 94a4041f5b186f73f2fe70fc245f2cbca3a8ab0f..cbcad1a0a8f98470ad7849ca4bb3bca856d112f9 100644
--- a/package_manager/tests/src/Kernel/PackageManagerKernelTestBase.php
+++ b/package_manager/tests/src/Kernel/PackageManagerKernelTestBase.php
@@ -29,6 +29,8 @@ use Symfony\Component\DependencyInjection\Definition;
 
 /**
  * Base class for kernel tests of Package Manager's functionality.
+ *
+ * @internal
  */
 abstract class PackageManagerKernelTestBase extends KernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PathExcluder/GitExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/GitExcluderTest.php
index 4da701a076e24de9139eeb7ed7cfadeff1e24a55..0dc8a8c6ba54e6d599a72b7847cad83183892081 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/GitExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/GitExcluderTest.php
@@ -6,8 +6,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\GitExcluder
- *
  * @group package_manager
+ * @internal
  */
 class GitExcluderTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PathExcluder/NodeModulesExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/NodeModulesExcluderTest.php
index 006e207126152f4d2e77b0f965905fecbe5b0aed..2317185307c4045e6ee76c0c2bb325c79e9a9948 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/NodeModulesExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/NodeModulesExcluderTest.php
@@ -6,8 +6,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\NodeModulesExcluder
- *
  * @group package_manager
+ * @internal
  */
 class NodeModulesExcluderTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PathExcluder/SiteConfigurationExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/SiteConfigurationExcluderTest.php
index 385e6132e6ab9899a838ae1c180cce1d84ebe8a7..933b8f959f0ae7973e032e4cc19081a3d99da8e7 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/SiteConfigurationExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/SiteConfigurationExcluderTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\SiteConfigurationExcluder
- *
  * @group package_manager
+ * @internal
  */
 class SiteConfigurationExcluderTest extends PackageManagerKernelTestBase {
 
@@ -50,7 +50,9 @@ class SiteConfigurationExcluderTest extends PackageManagerKernelTestBase {
     $site_path = 'sites/example.com';
 
     // Update the event subscribers' dependencies.
-    $this->container->get('package_manager.site_configuration_excluder')->sitePath = $site_path;
+    /** @var \Drupal\Tests\package_manager\Kernel\PathExcluder\TestSiteConfigurationExcluder $site_configuration_excluder */
+    $site_configuration_excluder = $this->container->get('package_manager.site_configuration_excluder');
+    $site_configuration_excluder->sitePath = $site_path;
 
     $stage = $this->createStage();
     $stage->create();
diff --git a/package_manager/tests/src/Kernel/PathExcluder/SiteFilesExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/SiteFilesExcluderTest.php
index 059c3115eb4586f293a4f692f07529a1a72065c9..db680b143f98df5a97c0dff010d31d238e5a90fe 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/SiteFilesExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/SiteFilesExcluderTest.php
@@ -6,8 +6,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\SiteFilesExcluder
- *
  * @group package_manager
+ * @internal
  */
 class SiteFilesExcluderTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PathExcluder/SqliteDatabaseExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/SqliteDatabaseExcluderTest.php
index f000f7e87c47ad5fa1c554598e2ed9ffd9faf2d7..6dd086d8f274175e9dbfbe9362ff1685d4bfafea 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/SqliteDatabaseExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/SqliteDatabaseExcluderTest.php
@@ -10,8 +10,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\SqliteDatabaseExcluder
- *
  * @group package_manager
+ * @internal
  */
 class SqliteDatabaseExcluderTest extends PackageManagerKernelTestBase {
 
@@ -47,8 +47,9 @@ class SqliteDatabaseExcluderTest extends PackageManagerKernelTestBase {
     $database->driver()->willReturn('sqlite');
     $database->getConnectionOptions()->willReturn($connection_options);
 
-    $this->container->get('package_manager.sqlite_excluder')
-      ->database = $database->reveal();
+    /** @var \Drupal\Tests\package_manager\Kernel\PathExcluder\TestSiteConfigurationExcluder $sqlite_excluder */
+    $sqlite_excluder = $this->container->get('package_manager.sqlite_excluder');
+    $sqlite_excluder->database = $database->reveal();
   }
 
   /**
diff --git a/package_manager/tests/src/Kernel/PathExcluder/TestSiteExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/TestSiteExcluderTest.php
index 4b53ba79ef589e3c5f2b076013bd0d02db381379..88e780f77d33eee63fcf6a77203aa1869809e564 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/TestSiteExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/TestSiteExcluderTest.php
@@ -6,8 +6,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\TestSiteExcluder
- *
  * @group package_manager
+ * @internal
  */
 class TestSiteExcluderTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PathExcluder/VendorHardeningExcluderTest.php b/package_manager/tests/src/Kernel/PathExcluder/VendorHardeningExcluderTest.php
index 93218424562e532910722ebcff4e73da2160b8e2..88a1202749c4c0d5b380997e2362b4cda271d3d9 100644
--- a/package_manager/tests/src/Kernel/PathExcluder/VendorHardeningExcluderTest.php
+++ b/package_manager/tests/src/Kernel/PathExcluder/VendorHardeningExcluderTest.php
@@ -6,8 +6,8 @@ use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;
 
 /**
  * @covers \Drupal\package_manager\PathExcluder\VendorHardeningExcluder
- *
  * @group package_manager
+ * @internal
  */
 class VendorHardeningExcluderTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php b/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php
index 192073a644f7784a7bc048ff1374c73ae116b89c..1308c2c17e188f125b71078608e75c49666c817b 100644
--- a/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php
+++ b/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php
@@ -7,8 +7,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\PendingUpdatesValidator
- *
  * @group package_manager
+ * @internal
  */
 class PendingUpdatesValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/ProjectInfoTest.php b/package_manager/tests/src/Kernel/ProjectInfoTest.php
index 402262378625165c52f7360389d53a2375afdbeb..b9924557a1bd3eebfd6c80bd937d784fbacb5bae 100644
--- a/package_manager/tests/src/Kernel/ProjectInfoTest.php
+++ b/package_manager/tests/src/Kernel/ProjectInfoTest.php
@@ -6,8 +6,8 @@ use Drupal\package_manager\ProjectInfo;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\ProjectInfo
- *
  * @group automatic_updates
+ * @internal
  */
 class ProjectInfoTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/ServicesTest.php b/package_manager/tests/src/Kernel/ServicesTest.php
index db6f8628f1bc7da4a0cc40f13d1123fdf7bc930a..bac20c469bbf2c543aad8ad86d89abe1bf039c09 100644
--- a/package_manager/tests/src/Kernel/ServicesTest.php
+++ b/package_manager/tests/src/Kernel/ServicesTest.php
@@ -12,6 +12,7 @@ use PhpTuf\ComposerStager\Infrastructure\Service\Finder\ExecutableFinderInterfac
  * Tests that Package Manager services are wired correctly.
  *
  * @group package_manager
+ * @internal
  */
 class ServicesTest extends KernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/SettingsValidatorTest.php b/package_manager/tests/src/Kernel/SettingsValidatorTest.php
index 3a4df2b119272747d743957931a1e961dc0382f6..c737cad34d4f8a8d2c23ffde182493e0fc613ab3 100644
--- a/package_manager/tests/src/Kernel/SettingsValidatorTest.php
+++ b/package_manager/tests/src/Kernel/SettingsValidatorTest.php
@@ -7,8 +7,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\SettingsValidator
- *
  * @group package_manager
+ * @internal
  */
 class SettingsValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/StageEventsTest.php b/package_manager/tests/src/Kernel/StageEventsTest.php
index 2161052f46a2b18155ea2af778c1e15d0d1f2aff..37a7d5aab3df745249fdf4d458b1822deb257c86 100644
--- a/package_manager/tests/src/Kernel/StageEventsTest.php
+++ b/package_manager/tests/src/Kernel/StageEventsTest.php
@@ -23,8 +23,8 @@ use Symfony\Component\EventDispatcher\EventSubscriberInterface;
  * Tests that the staging area fires events during its lifecycle.
  *
  * @covers \Drupal\package_manager\Event\StageEvent
- *
  * @group package_manager
+ * @internal
  */
 class StageEventsTest extends PackageManagerKernelTestBase implements EventSubscriberInterface {
 
diff --git a/package_manager/tests/src/Kernel/StageOwnershipTest.php b/package_manager/tests/src/Kernel/StageOwnershipTest.php
index 84f465782f5e7277428bb8bbcb6f459d3a06aedb..28b084db0cc214499b323e53a7895f2a2d6913a8 100644
--- a/package_manager/tests/src/Kernel/StageOwnershipTest.php
+++ b/package_manager/tests/src/Kernel/StageOwnershipTest.php
@@ -17,6 +17,7 @@ use ColinODell\PsrTestLogger\TestLogger;
  * Tests that ownership of the stage is enforced.
  *
  * @group package_manager
+ * @internal
  */
 class StageOwnershipTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/StageTest.php b/package_manager/tests/src/Kernel/StageTest.php
index 61cf2a80ec53a6c5349601d6a673a9c56af5680a..0713fd419595f7c7dfa4ac6e2b6a153e521f96c1 100644
--- a/package_manager/tests/src/Kernel/StageTest.php
+++ b/package_manager/tests/src/Kernel/StageTest.php
@@ -24,10 +24,9 @@ use ColinODell\PsrTestLogger\TestLogger;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\Stage
- *
  * @covers \Drupal\package_manager\PackageManagerUninstallValidator
- *
  * @group package_manager
+ * @internal
  */
 class StageTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/StageValidationExceptionTest.php b/package_manager/tests/src/Kernel/StageValidationExceptionTest.php
index 0bacff558971325f1c38c2a1630e0c4f9dc6a383..d905f232144d1cefdc2b401f3b5914a1d8073443 100644
--- a/package_manager/tests/src/Kernel/StageValidationExceptionTest.php
+++ b/package_manager/tests/src/Kernel/StageValidationExceptionTest.php
@@ -9,8 +9,8 @@ use Drupal\package_manager_test_validation\EventSubscriber\TestSubscriber;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\Exception\StageValidationException
- *
  * @group package_manager
+ * @internal
  */
 class StageValidationExceptionTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/StagedDBUpdateValidatorTest.php b/package_manager/tests/src/Kernel/StagedDBUpdateValidatorTest.php
index ff17b6c57987d6bbbfdacfb979fa0d17af96b091..ede72c4874801ec934aa4c25444312c6ccf89969 100644
--- a/package_manager/tests/src/Kernel/StagedDBUpdateValidatorTest.php
+++ b/package_manager/tests/src/Kernel/StagedDBUpdateValidatorTest.php
@@ -6,8 +6,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\StagedDBUpdateValidator
- *
  * @group package_manager
+ * @internal
  */
 class StagedDBUpdateValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/StatusCheckTraitTest.php b/package_manager/tests/src/Kernel/StatusCheckTraitTest.php
index 314826fd1949c6987d81186f6268a01922a64aa1..5173eab284983f3f745ce291c073b80a7cc5bcd8 100644
--- a/package_manager/tests/src/Kernel/StatusCheckTraitTest.php
+++ b/package_manager/tests/src/Kernel/StatusCheckTraitTest.php
@@ -8,8 +8,8 @@ use Drupal\package_manager\StatusCheckTrait;
 
 /**
  * @covers \Drupal\package_manager\StatusCheckTrait
- *
  * @group package_manager
+ * @internal
  */
 class StatusCheckTraitTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/SupportedReleaseValidatorTest.php b/package_manager/tests/src/Kernel/SupportedReleaseValidatorTest.php
index 58832ce39cdb7db9e6be1113719ca52e31b2d57c..11e1c00b6eb85b977ad7b5f771225571c078ea9a 100644
--- a/package_manager/tests/src/Kernel/SupportedReleaseValidatorTest.php
+++ b/package_manager/tests/src/Kernel/SupportedReleaseValidatorTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\package_manager\Traits\FixtureUtilityTrait;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\Validator\SupportedReleaseValidator
- *
  * @group package_manager
+ * @internal
  */
 class SupportedReleaseValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/SymlinkValidatorTest.php b/package_manager/tests/src/Kernel/SymlinkValidatorTest.php
index 8773b1ecfc8d04acfce4960aed43e23c5a526a20..351af83ee2febb8f7a18899041d49a3c468a4496 100644
--- a/package_manager/tests/src/Kernel/SymlinkValidatorTest.php
+++ b/package_manager/tests/src/Kernel/SymlinkValidatorTest.php
@@ -16,8 +16,8 @@ use Prophecy\Argument;
 
 /**
  * @covers \Drupal\package_manager\Validator\SymlinkValidator
- *
  * @group package_manager
+ * @internal
  */
 class SymlinkValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/WritableFileSystemValidatorTest.php b/package_manager/tests/src/Kernel/WritableFileSystemValidatorTest.php
index 4005a8a0f3411a7f0c3f99aae869bb21ad3b7952..bbef90d1dd23f5f55fa76132cc5bd154f302b937 100644
--- a/package_manager/tests/src/Kernel/WritableFileSystemValidatorTest.php
+++ b/package_manager/tests/src/Kernel/WritableFileSystemValidatorTest.php
@@ -15,8 +15,8 @@ use Symfony\Component\Filesystem\Filesystem;
  * @see \Drupal\Tests\automatic_updates\Build\CoreUpdateTest::assertReadOnlyFileSystemError()
  *
  * @covers \Drupal\package_manager\Validator\WritableFileSystemValidator
- *
  * @group package_manager
+ * @internal
  */
 class WritableFileSystemValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Kernel/XdebugValidatorTest.php b/package_manager/tests/src/Kernel/XdebugValidatorTest.php
index eaf9cbfc4292ab039511357e9266328a3b1552a4..43ce87e044fa2c2e9242c770b9fc157b1682891b 100644
--- a/package_manager/tests/src/Kernel/XdebugValidatorTest.php
+++ b/package_manager/tests/src/Kernel/XdebugValidatorTest.php
@@ -6,8 +6,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * @covers \Drupal\package_manager\Validator\XdebugValidator
- *
  * @group package_manager
+ * @internal
  */
 class XdebugValidatorTest extends PackageManagerKernelTestBase {
 
diff --git a/package_manager/tests/src/Traits/FixtureUtilityTrait.php b/package_manager/tests/src/Traits/FixtureUtilityTrait.php
index 351d941892cd630c2c0489b759905c9a7efdc658..01eb6a689be1e8f94e30b7b985069740eb596e2b 100644
--- a/package_manager/tests/src/Traits/FixtureUtilityTrait.php
+++ b/package_manager/tests/src/Traits/FixtureUtilityTrait.php
@@ -10,6 +10,8 @@ use Symfony\Component\Finder\Iterator\RecursiveDirectoryIterator;
 
 /**
  * A utility for all things fixtures.
+ *
+ * @internal
  */
 trait FixtureUtilityTrait {
 
diff --git a/package_manager/tests/src/Traits/InfoYmlConverterTrait.php b/package_manager/tests/src/Traits/InfoYmlConverterTrait.php
index 26dd39e86b4b8a6daee7315c2dfe3969de1ae944..a49d9f1bb1907af24b8b5ff20cafa8d6cf3fd5c7 100644
--- a/package_manager/tests/src/Traits/InfoYmlConverterTrait.php
+++ b/package_manager/tests/src/Traits/InfoYmlConverterTrait.php
@@ -11,6 +11,8 @@ use org\bovigo\vfs\visitor\vfsStreamAbstractVisitor;
 
 /**
  * Common methods to convert info.yml file that will pass core coding standards.
+ *
+ * @internal
  */
 trait InfoYmlConverterTrait {
 
diff --git a/package_manager/tests/src/Traits/PackageManagerBypassTestTrait.php b/package_manager/tests/src/Traits/PackageManagerBypassTestTrait.php
index 854b0e996ee7ea41e7fa5e7d6aff171690bb8dcd..6c4c495609d3c73bfc0f5d8699a51e6a979fa89b 100644
--- a/package_manager/tests/src/Traits/PackageManagerBypassTestTrait.php
+++ b/package_manager/tests/src/Traits/PackageManagerBypassTestTrait.php
@@ -6,6 +6,8 @@ namespace Drupal\Tests\package_manager\Traits;
 
 /**
  * Common functions for testing using the package_manager_bypass module.
+ *
+ * @internal
  */
 trait PackageManagerBypassTestTrait {
 
diff --git a/package_manager/tests/src/Traits/ValidationTestTrait.php b/package_manager/tests/src/Traits/ValidationTestTrait.php
index 13042bfe1890afecfb0793308af3cc34ab8fab83..e7d558e29343eb5d98795e9b361931a3a3f88fcc 100644
--- a/package_manager/tests/src/Traits/ValidationTestTrait.php
+++ b/package_manager/tests/src/Traits/ValidationTestTrait.php
@@ -8,6 +8,8 @@ use Drupal\package_manager\ValidationResult;
 
 /**
  * Contains helpful methods for testing stage validators.
+ *
+ * @internal
  */
 trait ValidationTestTrait {
 
diff --git a/package_manager/tests/src/Unit/ComposerUtilityTest.php b/package_manager/tests/src/Unit/ComposerUtilityTest.php
index 80f829b5c90626dd472d5260d43a2feb07ee0fb2..54107de9d9dcbed186cf3f2dcc6aa6f53b9d2f40 100644
--- a/package_manager/tests/src/Unit/ComposerUtilityTest.php
+++ b/package_manager/tests/src/Unit/ComposerUtilityTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\ComposerUtility
- *
  * @group package_manager
+ * @internal
  */
 class ComposerUtilityTest extends UnitTestCase {
 
diff --git a/package_manager/tests/src/Unit/InstalledPackagesDataTest.php b/package_manager/tests/src/Unit/InstalledPackagesDataTest.php
index eb4a859e7b4f9f3cfb3bb9a61dc43dc4c7594d9b..566e11502fdc8b9a79bb0e5abda9a06d65c78850 100644
--- a/package_manager/tests/src/Unit/InstalledPackagesDataTest.php
+++ b/package_manager/tests/src/Unit/InstalledPackagesDataTest.php
@@ -13,6 +13,7 @@ use Drupal\Tests\UnitTestCase;
  * internal structure changes in a way that would break our functionality.
  *
  * @group package_manager
+ * @internal
  */
 class InstalledPackagesDataTest extends UnitTestCase {
 
diff --git a/package_manager/tests/src/Unit/PathLocatorTest.php b/package_manager/tests/src/Unit/PathLocatorTest.php
index 5f4157f284b96a45d36fdaa08f495a7102b4d467..5bf9b0dd04bda1bc65373ab136a9e98a1ccd155d 100644
--- a/package_manager/tests/src/Unit/PathLocatorTest.php
+++ b/package_manager/tests/src/Unit/PathLocatorTest.php
@@ -9,8 +9,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\PathLocator
- *
  * @group package_manager
+ * @internal
  */
 class PathLocatorTest extends UnitTestCase {
 
diff --git a/package_manager/tests/src/Unit/ProcessFactoryTest.php b/package_manager/tests/src/Unit/ProcessFactoryTest.php
index c2e8ddd308975daef592c4aba3f9711921b9d610..d0d646d756e6d4a614e03d98005a4fe6cb200fa3 100644
--- a/package_manager/tests/src/Unit/ProcessFactoryTest.php
+++ b/package_manager/tests/src/Unit/ProcessFactoryTest.php
@@ -7,8 +7,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\ProcessFactory
- *
  * @group automatic_updates
+ * @internal
  */
 class ProcessFactoryTest extends UnitTestCase {
 
diff --git a/package_manager/tests/src/Unit/RequireEventTraitTest.php b/package_manager/tests/src/Unit/RequireEventTraitTest.php
index f65df4d80a6ed1b6aaa62d5ce52ce1772545a49b..b28ecc53177ac6ad2e735f1f71d3acf067736126 100644
--- a/package_manager/tests/src/Unit/RequireEventTraitTest.php
+++ b/package_manager/tests/src/Unit/RequireEventTraitTest.php
@@ -6,8 +6,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\package_manager\Event\RequireEventTrait
- *
  * @group package_manager
+ * @internal
  */
 class RequireEventTraitTest extends UnitTestCase {
 
diff --git a/package_manager/tests/src/Unit/ValidationResultTest.php b/package_manager/tests/src/Unit/ValidationResultTest.php
index 3ae93eacc8575f292d7c84f44513ad03e5de1e8d..cdf0a6dfaa07e122d25c76fe3ffd819925aeba62 100644
--- a/package_manager/tests/src/Unit/ValidationResultTest.php
+++ b/package_manager/tests/src/Unit/ValidationResultTest.php
@@ -9,8 +9,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\ValidationResult
- *
  * @group package_manager
+ * @internal
  */
 class ValidationResultTest extends UnitTestCase {
 
diff --git a/tests/src/Build/CoreUpdateTest.php b/tests/src/Build/CoreUpdateTest.php
index 6664811825b20e92259829537d33da4d9d9ac0b3..1355482a19909939782985bde86aecd168ea8d7d 100644
--- a/tests/src/Build/CoreUpdateTest.php
+++ b/tests/src/Build/CoreUpdateTest.php
@@ -9,6 +9,7 @@ use Drupal\Tests\WebAssert;
  * Tests an end-to-end update of Drupal core.
  *
  * @group automatic_updates
+ * @internal
  */
 class CoreUpdateTest extends UpdateTestBase {
 
diff --git a/tests/src/Build/UpdateTestBase.php b/tests/src/Build/UpdateTestBase.php
index c986815ce350a0907a43e6ae9082c2aef3899b81..ddafd13da59b98e6e2f199e0c13badcdf90feb5a 100644
--- a/tests/src/Build/UpdateTestBase.php
+++ b/tests/src/Build/UpdateTestBase.php
@@ -9,6 +9,8 @@ use Drupal\Tests\package_manager\Build\TemplateProjectTestBase;
 
 /**
  * Base class for tests that perform in-place updates.
+ *
+ * @internal
  */
 abstract class UpdateTestBase extends TemplateProjectTestBase {
 
diff --git a/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php b/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php
index 29435f339d0ab329abf422fe7e9dcde279012093..fdd355e03ddc5f28024b8f08e11a17c7350b7a90 100644
--- a/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php
+++ b/tests/src/Functional/AutomaticUpdatesFunctionalTestBase.php
@@ -13,6 +13,8 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
  * Base class for functional tests of the Automatic Updates module.
+ *
+ * @internal
  */
 abstract class AutomaticUpdatesFunctionalTestBase extends BrowserTestBase {
 
diff --git a/tests/src/Functional/AvailableUpdatesReportTest.php b/tests/src/Functional/AvailableUpdatesReportTest.php
index 896c162199d92fc963fc61a045ed600b218381ce..0ab736335f0069b156d6c6216cb4479f0e6c893e 100644
--- a/tests/src/Functional/AvailableUpdatesReportTest.php
+++ b/tests/src/Functional/AvailableUpdatesReportTest.php
@@ -8,6 +8,7 @@ use Drupal\Core\Url;
  * Tests changes to the Available Updates report provided by the Update module.
  *
  * @group automatic_updates
+ * @internal
  */
 class AvailableUpdatesReportTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Functional/ClickableHelpTest.php b/tests/src/Functional/ClickableHelpTest.php
index 0a8764acc04120c7e6b421ba15caf5f597f0acc0..a87dde2e1f9e7779bcdca041be72c5a0020b77e8 100644
--- a/tests/src/Functional/ClickableHelpTest.php
+++ b/tests/src/Functional/ClickableHelpTest.php
@@ -8,6 +8,7 @@ namespace Drupal\Tests\automatic_updates\Functional;
  * Tests package manager help link is clickable.
  *
  * @group automatic_updates
+ * @internal
  */
 class ClickableHelpTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Functional/DeprecatedRoutesTest.php b/tests/src/Functional/DeprecatedRoutesTest.php
index 630b6f553820f237a48c684a383e94e34aae8f40..b52c55d95df2a31e10c8c8b784764809f7704906 100644
--- a/tests/src/Functional/DeprecatedRoutesTest.php
+++ b/tests/src/Functional/DeprecatedRoutesTest.php
@@ -7,9 +7,9 @@ use Drupal\Core\Url;
 /**
  * @covers \Drupal\automatic_updates\Controller\UpdateController::redirectDeprecatedRoute
  * @covers \Drupal\automatic_updates\Routing\RouteSubscriber
- *
  * @group automatic_updates
  * @group legacy
+ * @internal
  */
 class DeprecatedRoutesTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Functional/HelpPageTest.php b/tests/src/Functional/HelpPageTest.php
index 0061daff86cfe8dea857d399265a987a5fe0b4fe..0cf65bef43b9c4ed2d2ec29356cd5b69a301448a 100644
--- a/tests/src/Functional/HelpPageTest.php
+++ b/tests/src/Functional/HelpPageTest.php
@@ -6,6 +6,7 @@ use Drupal\Tests\BrowserTestBase;
 
 /**
  * @group automatic_updates
+ * @internal
  */
 class HelpPageTest extends BrowserTestBase {
 
diff --git a/tests/src/Functional/StatusCheckTest.php b/tests/src/Functional/StatusCheckTest.php
index 9e2c6ae191c5cb2983587c8fa83431d69e6f2f3d..f3ce4e248779458cef5a5d7ba68db287a9ea8d14 100644
--- a/tests/src/Functional/StatusCheckTest.php
+++ b/tests/src/Functional/StatusCheckTest.php
@@ -17,6 +17,7 @@ use Drupal\Tests\Traits\Core\CronRunTrait;
  * Tests status checks.
  *
  * @group automatic_updates
+ * @internal
  */
 class StatusCheckTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Functional/UpdateLockTest.php b/tests/src/Functional/UpdateLockTest.php
index 37ef6a44595c95a91af7f8c7c4f358518699d478..c68c25b2e291b0c62e315540eb77c0816aa9ee2c 100644
--- a/tests/src/Functional/UpdateLockTest.php
+++ b/tests/src/Functional/UpdateLockTest.php
@@ -8,6 +8,7 @@ use Drupal\package_manager_bypass\Stager;
  * Tests that only one Automatic Update operation can be performed at a time.
  *
  * @group automatic_updates
+ * @internal
  */
 class UpdateLockTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Functional/UpdatePathTest.php b/tests/src/Functional/UpdatePathTest.php
index e13e498e9717c2de0930d265208554de4d1c3dbe..a0e9f3b6aeed6efed62ce8f68c452be12d7abf75 100644
--- a/tests/src/Functional/UpdatePathTest.php
+++ b/tests/src/Functional/UpdatePathTest.php
@@ -7,6 +7,7 @@ use Drupal\FunctionalTests\Update\UpdatePathTestBase;
 
 /**
  * @group automatic_updates
+ * @internal
  */
 class UpdatePathTest extends UpdatePathTestBase {
 
diff --git a/tests/src/Functional/UpdaterFormNoRecommendedReleaseMessageTest.php b/tests/src/Functional/UpdaterFormNoRecommendedReleaseMessageTest.php
index 455fe0d806c8739841de3fa05c0d5dd4b81ecfd6..6d8d7bbcc7e4b3439529dee68e28bf5f3ac33a47 100644
--- a/tests/src/Functional/UpdaterFormNoRecommendedReleaseMessageTest.php
+++ b/tests/src/Functional/UpdaterFormNoRecommendedReleaseMessageTest.php
@@ -6,6 +6,7 @@ namespace Drupal\Tests\automatic_updates\Functional;
  * Tests messages on the updater form when there is no recommended release.
  *
  * @group automatic_updates
+ * @internal
  */
 class UpdaterFormNoRecommendedReleaseMessageTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Functional/UpdaterFormTest.php b/tests/src/Functional/UpdaterFormTest.php
index 722d5e99885a8d1367ce4ebabc7aef8707127d2f..424325cb9ebcfb952579479f3c2cc7298fc9b1fc 100644
--- a/tests/src/Functional/UpdaterFormTest.php
+++ b/tests/src/Functional/UpdaterFormTest.php
@@ -20,8 +20,8 @@ use Drupal\Tests\package_manager\Traits\PackageManagerBypassTestTrait;
 
 /**
  * @covers \Drupal\automatic_updates\Form\UpdaterForm
- *
  * @group automatic_updates
+ * @internal
  */
 class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
 
diff --git a/tests/src/Kernel/AutomaticUpdatesKernelTestBase.php b/tests/src/Kernel/AutomaticUpdatesKernelTestBase.php
index e8061954838af8e94ec73fb9ccebcfbcb9dbd033..ad69a1c28474cdd1dd912b9b2eff78adead01c44 100644
--- a/tests/src/Kernel/AutomaticUpdatesKernelTestBase.php
+++ b/tests/src/Kernel/AutomaticUpdatesKernelTestBase.php
@@ -14,6 +14,8 @@ use Drupal\Tests\package_manager\Kernel\TestStageTrait;
 
 /**
  * Base class for kernel tests of the Automatic Updates module.
+ *
+ * @internal
  */
 abstract class AutomaticUpdatesKernelTestBase extends PackageManagerKernelTestBase {
 
diff --git a/tests/src/Kernel/CronUpdaterTest.php b/tests/src/Kernel/CronUpdaterTest.php
index d1c6d84c697622d76ff9319ea69e98c48295ef10..5cfa075ff7ea986068504ef9c0e6390703c1d39b 100644
--- a/tests/src/Kernel/CronUpdaterTest.php
+++ b/tests/src/Kernel/CronUpdaterTest.php
@@ -30,8 +30,8 @@ use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 /**
  * @covers \Drupal\automatic_updates\CronUpdater
  * @covers \automatic_updates_form_update_settings_alter
- *
  * @group automatic_updates
+ * @internal
  */
 class CronUpdaterTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/ReadinessCheckTest.php b/tests/src/Kernel/ReadinessCheckTest.php
index c940737370e6c9cdcacca1382e72e88c118ef26a..24f23749bf7694fd168d4abf11659d7bbc59372f 100644
--- a/tests/src/Kernel/ReadinessCheckTest.php
+++ b/tests/src/Kernel/ReadinessCheckTest.php
@@ -9,6 +9,7 @@ use Drupal\package_manager\StatusCheckTrait;
  * Tests that running readiness checks raises deprecation notices.
  *
  * @group legacy
+ * @internal
  */
 class ReadinessCheckTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/ReleaseChooserTest.php b/tests/src/Kernel/ReleaseChooserTest.php
index 79d60367d2b3f3386c176839f83f5aca85e2d88f..08340f1d69d25cc5ff50680ca356ac35868b7f8c 100644
--- a/tests/src/Kernel/ReleaseChooserTest.php
+++ b/tests/src/Kernel/ReleaseChooserTest.php
@@ -7,8 +7,8 @@ use Drupal\update\ProjectRelease;
 
 /**
  * @coversDefaultClass \Drupal\automatic_updates\ReleaseChooser
- *
  * @group automatic_updates
+ * @internal
  */
 class ReleaseChooserTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/CronFrequencyValidatorTest.php b/tests/src/Kernel/StatusCheck/CronFrequencyValidatorTest.php
index e455c3b31a9091086698e5509dfc4baefba4b574..693478a9b4a1635034c9f9d46944d6ab46cf1fb4 100644
--- a/tests/src/Kernel/StatusCheck/CronFrequencyValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/CronFrequencyValidatorTest.php
@@ -10,8 +10,8 @@ use PHPUnit\Framework\AssertionFailedError;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\CronFrequencyValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class CronFrequencyValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/CronServerValidatorTest.php b/tests/src/Kernel/StatusCheck/CronServerValidatorTest.php
index 5c39b0159655e324ba8299768ee7a6b5eadd8fc1..13f525cc88a32e93f0addd5fd8f8ce07a1d9c2b0 100644
--- a/tests/src/Kernel/StatusCheck/CronServerValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/CronServerValidatorTest.php
@@ -13,8 +13,8 @@ use ColinODell\PsrTestLogger\TestLogger;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\CronServerValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class CronServerValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/ScaffoldFilePermissionsValidatorTest.php b/tests/src/Kernel/StatusCheck/ScaffoldFilePermissionsValidatorTest.php
index b4e28a735caea36781a5df622d74a79bfbfb2390..8a7ec476970d7e8dd52883463fa4401b45901e3c 100644
--- a/tests/src/Kernel/StatusCheck/ScaffoldFilePermissionsValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/ScaffoldFilePermissionsValidatorTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\automatic_updates\Kernel\AutomaticUpdatesKernelTestBase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\ScaffoldFilePermissionsValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class ScaffoldFilePermissionsValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/StagedDatabaseUpdateValidatorTest.php b/tests/src/Kernel/StatusCheck/StagedDatabaseUpdateValidatorTest.php
index 8b5e709541e6f78f433b75c38ad6bc77b9a3a188..db2ced0f1bdc166351aa3cf07ac152807328b793 100644
--- a/tests/src/Kernel/StatusCheck/StagedDatabaseUpdateValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/StagedDatabaseUpdateValidatorTest.php
@@ -9,8 +9,8 @@ use ColinODell\PsrTestLogger\TestLogger;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\StagedDatabaseUpdateValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class StagedDatabaseUpdateValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/StagedProjectsValidatorTest.php b/tests/src/Kernel/StatusCheck/StagedProjectsValidatorTest.php
index 5cb6ad6d7b4e51c47fda7a924a8c58564011e511..fcad516f003b9b3d8ce442cb82ec77160557a0f0 100644
--- a/tests/src/Kernel/StatusCheck/StagedProjectsValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/StagedProjectsValidatorTest.php
@@ -10,8 +10,8 @@ use Drupal\Tests\package_manager\Traits\FixtureUtilityTrait;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\StagedProjectsValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class StagedProjectsValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/StatusCheckFailureEmailTest.php b/tests/src/Kernel/StatusCheck/StatusCheckFailureEmailTest.php
index 3e9df9de557d174eeeaa2178703343e9fcd1cb3c..d69c1e6021732b86450ff39c3702ca63e9ee8285 100644
--- a/tests/src/Kernel/StatusCheck/StatusCheckFailureEmailTest.php
+++ b/tests/src/Kernel/StatusCheck/StatusCheckFailureEmailTest.php
@@ -16,8 +16,8 @@ use Drupal\Tests\automatic_updates\Traits\EmailNotificationsTestTrait;
  * Tests status check failure notification emails during cron runs.
  *
  * @group automatic_updates
- *
  * @covers \Drupal\automatic_updates\StatusCheckMailer
+ * @internal
  */
 class StatusCheckFailureEmailTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/StatusCheckerTest.php b/tests/src/Kernel/StatusCheck/StatusCheckerTest.php
index 03d1d926c9800e1defd072c7d546859fa2001f52..566800e9bf35bbe1ab404d06cc31889f118d30ea 100644
--- a/tests/src/Kernel/StatusCheck/StatusCheckerTest.php
+++ b/tests/src/Kernel/StatusCheck/StatusCheckerTest.php
@@ -12,8 +12,8 @@ use Drupal\Tests\automatic_updates\Kernel\AutomaticUpdatesKernelTestBase;
 
 /**
  * @coversDefaultClass \Drupal\automatic_updates\Validation\StatusChecker
- *
  * @group automatic_updates
+ * @internal
  */
 class StatusCheckerTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/VersionPolicy/SupportedBranchInstalledTest.php b/tests/src/Kernel/StatusCheck/VersionPolicy/SupportedBranchInstalledTest.php
index e2d6c94f7717b2b6a956d26a84028971bdee4846..30fe297f8caec4f2f9c8432b975c6fffe11413f4 100644
--- a/tests/src/Kernel/StatusCheck/VersionPolicy/SupportedBranchInstalledTest.php
+++ b/tests/src/Kernel/StatusCheck/VersionPolicy/SupportedBranchInstalledTest.php
@@ -7,8 +7,8 @@ use Drupal\Tests\automatic_updates\Kernel\AutomaticUpdatesKernelTestBase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\SupportedBranchInstalled
- *
  * @group automatic_updates
+ * @internal
  */
 class SupportedBranchInstalledTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/VersionPolicyValidatorTest.php b/tests/src/Kernel/StatusCheck/VersionPolicyValidatorTest.php
index 8781c4dcdd20ea5379b4464c768a86627b7968e9..515b0d75b6d9d96e709d0c1e8e8a6279b5ec3c55 100644
--- a/tests/src/Kernel/StatusCheck/VersionPolicyValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/VersionPolicyValidatorTest.php
@@ -11,8 +11,8 @@ use Drupal\Tests\automatic_updates\Kernel\AutomaticUpdatesKernelTestBase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicyValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class VersionPolicyValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/StatusCheck/XdebugValidatorTest.php b/tests/src/Kernel/StatusCheck/XdebugValidatorTest.php
index 7f23751d02f9d78b3a9ac6ee5c85bac80967d151..5327b101a6e8d4f21ca8258dc798d96ab3b2572c 100644
--- a/tests/src/Kernel/StatusCheck/XdebugValidatorTest.php
+++ b/tests/src/Kernel/StatusCheck/XdebugValidatorTest.php
@@ -11,8 +11,8 @@ use ColinODell\PsrTestLogger\TestLogger;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\XdebugValidator
- *
  * @group automatic_updates
+ * @internal
  */
 class XdebugValidatorTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/UpdaterTest.php b/tests/src/Kernel/UpdaterTest.php
index 693d12bcce19c1c5f26b66ee33ac0c0fb8d1e666..2b365a60fd2bb5a76601ea7716f184b76638308c 100644
--- a/tests/src/Kernel/UpdaterTest.php
+++ b/tests/src/Kernel/UpdaterTest.php
@@ -15,8 +15,8 @@ use PhpTuf\ComposerStager\Domain\Exception\InvalidArgumentException;
 
 /**
  * @coversDefaultClass \Drupal\automatic_updates\Updater
- *
  * @group automatic_updates
+ * @internal
  */
 class UpdaterTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Kernel/ValidationResultDisplayTraitTest.php b/tests/src/Kernel/ValidationResultDisplayTraitTest.php
index c3e0664df9887e249e9a355a4e10b342c5b0760c..319be3b8932302ec5829afe036559265024b7712 100644
--- a/tests/src/Kernel/ValidationResultDisplayTraitTest.php
+++ b/tests/src/Kernel/ValidationResultDisplayTraitTest.php
@@ -10,8 +10,8 @@ use Drupal\system\SystemManager;
 
 /**
  * @coversDefaultClass \Drupal\automatic_updates\Validation\ValidationResultDisplayTrait
- *
  * @group automatic_updates
+ * @internal
  */
 class ValidationResultDisplayTraitTest extends AutomaticUpdatesKernelTestBase {
 
diff --git a/tests/src/Traits/EmailNotificationsTestTrait.php b/tests/src/Traits/EmailNotificationsTestTrait.php
index 92e5e53cb073c592b0a1cace988d9c93bec6606c..0fdd39933a74c616d502fa03b178a347aa7f96b4 100644
--- a/tests/src/Traits/EmailNotificationsTestTrait.php
+++ b/tests/src/Traits/EmailNotificationsTestTrait.php
@@ -9,6 +9,8 @@ use Drupal\Tests\user\Traits\UserCreationTrait;
 
 /**
  * Contains helper methods for testing e-mail sent by Automatic Updates.
+ *
+ * @internal
  */
 trait EmailNotificationsTestTrait {
 
diff --git a/tests/src/Traits/ValidationTestTrait.php b/tests/src/Traits/ValidationTestTrait.php
index dcd5d85e45896d7cd97d0040515e9f924a41a49d..e0e88a60a243f5ed55307c2724834eeeb5d3014e 100644
--- a/tests/src/Traits/ValidationTestTrait.php
+++ b/tests/src/Traits/ValidationTestTrait.php
@@ -10,6 +10,8 @@ use Drupal\Tests\package_manager\Traits\ValidationTestTrait as PackageManagerVal
 
 /**
  * Common methods for testing validation.
+ *
+ * @internal
  */
 trait ValidationTestTrait {
 
diff --git a/tests/src/Traits/VersionPolicyTestTrait.php b/tests/src/Traits/VersionPolicyTestTrait.php
index b22baa95ed928002c795d21594e91dc7224b154a..d1fda5ef885bec84571b388dac4a69873a27d504 100644
--- a/tests/src/Traits/VersionPolicyTestTrait.php
+++ b/tests/src/Traits/VersionPolicyTestTrait.php
@@ -6,6 +6,8 @@ namespace Drupal\Tests\automatic_updates\Traits;
 
 /**
  * Common methods for testing version policy rules.
+ *
+ * @internal
  */
 trait VersionPolicyTestTrait {
 
diff --git a/tests/src/Unit/LegacyVersionUtilityTest.php b/tests/src/Unit/LegacyVersionUtilityTest.php
index 95d0edec25a35a3d006048fc5d464afd6db18d08..782602c8db98193b18672295cdd6c0f020f41e2d 100644
--- a/tests/src/Unit/LegacyVersionUtilityTest.php
+++ b/tests/src/Unit/LegacyVersionUtilityTest.php
@@ -7,8 +7,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @coversDefaultClass \Drupal\package_manager\LegacyVersionUtility
- *
  * @group automatic_updates
+ * @internal
  */
 class LegacyVersionUtilityTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/ForbidDevSnapshotTest.php b/tests/src/Unit/VersionPolicy/ForbidDevSnapshotTest.php
index b77cba12a6f68ccc41019d12ad9d4ab405dd83bb..4ce40968b804d60e0ac3d92904ee32a57dbd62b8 100644
--- a/tests/src/Unit/VersionPolicy/ForbidDevSnapshotTest.php
+++ b/tests/src/Unit/VersionPolicy/ForbidDevSnapshotTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\ForbidDevSnapshot
- *
  * @group automatic_updates
+ * @internal
  */
 class ForbidDevSnapshotTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/ForbidDowngradeTest.php b/tests/src/Unit/VersionPolicy/ForbidDowngradeTest.php
index f411b3fd1be1659524e9014a0eebed37077bf511..249cd81ee948ef43f5be9143e809b9030d2dd904 100644
--- a/tests/src/Unit/VersionPolicy/ForbidDowngradeTest.php
+++ b/tests/src/Unit/VersionPolicy/ForbidDowngradeTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\ForbidDowngrade
- *
  * @group automatic_updates
+ * @internal
  */
 class ForbidDowngradeTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/ForbidMinorUpdatesTest.php b/tests/src/Unit/VersionPolicy/ForbidMinorUpdatesTest.php
index fdc396c57d97614f0b864cc59afe90c7606b99d3..0e8e687ead2c818e2a54d250318bdef1a00526f6 100644
--- a/tests/src/Unit/VersionPolicy/ForbidMinorUpdatesTest.php
+++ b/tests/src/Unit/VersionPolicy/ForbidMinorUpdatesTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\ForbidMinorUpdates
- *
  * @group automatic_updates
+ * @internal
  */
 class ForbidMinorUpdatesTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/MajorVersionMatchTest.php b/tests/src/Unit/VersionPolicy/MajorVersionMatchTest.php
index 76c78598e6cc9ada10c6a94fc124a1e4039439b7..a24262ad6d65992ba44fd2654ac2a62866fdf4fd 100644
--- a/tests/src/Unit/VersionPolicy/MajorVersionMatchTest.php
+++ b/tests/src/Unit/VersionPolicy/MajorVersionMatchTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\MajorVersionMatch
- *
  * @group automatic_updates
+ * @internal
  */
 class MajorVersionMatchTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/MinorUpdatesEnabledTest.php b/tests/src/Unit/VersionPolicy/MinorUpdatesEnabledTest.php
index 9d5f5fbee4a4b90fa16ffba160a98757a91cf5d3..35442d46504e36ecf979137a670c6717bb16daf3 100644
--- a/tests/src/Unit/VersionPolicy/MinorUpdatesEnabledTest.php
+++ b/tests/src/Unit/VersionPolicy/MinorUpdatesEnabledTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\MinorUpdatesEnabled
- *
  * @group automatic_updates
+ * @internal
  */
 class MinorUpdatesEnabledTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/StableReleaseInstalledTest.php b/tests/src/Unit/VersionPolicy/StableReleaseInstalledTest.php
index fc135587f4bbe12d0c2ac2f009dba212800cc3f4..2f85f791494fb062a5cac27d891254e77c032224 100644
--- a/tests/src/Unit/VersionPolicy/StableReleaseInstalledTest.php
+++ b/tests/src/Unit/VersionPolicy/StableReleaseInstalledTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\StableReleaseInstalled
- *
  * @group automatic_updates
+ * @internal
  */
 class StableReleaseInstalledTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/TargetSecurityReleaseTest.php b/tests/src/Unit/VersionPolicy/TargetSecurityReleaseTest.php
index 3bc827f0ce8e6238aef652dbf3c4e025193e3d52..1b7570ff06d4f23b5780b28b9be26cb63d2c57b0 100644
--- a/tests/src/Unit/VersionPolicy/TargetSecurityReleaseTest.php
+++ b/tests/src/Unit/VersionPolicy/TargetSecurityReleaseTest.php
@@ -9,8 +9,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\TargetSecurityRelease
- *
  * @group automatic_updates
+ * @internal
  */
 class TargetSecurityReleaseTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/TargetVersionInstallableTest.php b/tests/src/Unit/VersionPolicy/TargetVersionInstallableTest.php
index 144d046e93f5ad7be2cddd62de3c1e10d4b64e1e..4bcb764a129d0eaf6034440691954d48597edda6 100644
--- a/tests/src/Unit/VersionPolicy/TargetVersionInstallableTest.php
+++ b/tests/src/Unit/VersionPolicy/TargetVersionInstallableTest.php
@@ -9,8 +9,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\TargetVersionInstallable
- *
  * @group automatic_updates
+ * @internal
  */
 class TargetVersionInstallableTest extends UnitTestCase {
 
diff --git a/tests/src/Unit/VersionPolicy/TargetVersionStableTest.php b/tests/src/Unit/VersionPolicy/TargetVersionStableTest.php
index 3cfa0454921513c6cb2326730011eaaaeace070d..d42fcd03158f6654f6afc42bacf7c2a290166840 100644
--- a/tests/src/Unit/VersionPolicy/TargetVersionStableTest.php
+++ b/tests/src/Unit/VersionPolicy/TargetVersionStableTest.php
@@ -8,8 +8,8 @@ use Drupal\Tests\UnitTestCase;
 
 /**
  * @covers \Drupal\automatic_updates\Validator\VersionPolicy\TargetVersionStable
- *
  * @group automatic_updates
+ * @internal
  */
 class TargetVersionStableTest extends UnitTestCase {