Issue #3364958: Stages should be destroyed in the background, during cron runs

package_manager/tests/src/Kernel/StageBaseTest.php

@@ -733,6 +733,12 @@ class StageBaseTest extends PackageManagerKernelTestBase {
     $this->assertTrue($stage->stageDirectoryExists());
   }
 
+  /**
+   * Tests that destroyed stage directories are actually deleted during cron.
+   *
+   * @covers ::destroy
+   * @covers \Drupal\package_manager\Plugin\QueueWorker\Cleaner
+   */
   public function testStageDirectoryDeletedDuringCron(): void {
     $stage = $this->createStage();
     $stage->create();