Issue #3316895: Create a test to prove our fake-site is error free starting point

package_manager/tests/src/Kernel/FakeSiteFixtureTest.php

+<?php
+
+namespace Drupal\Tests\package_manager\Kernel;
+
+/**
+ * Test that the 'fake-site' fixture is a valid starting point.
+ *
+ * @group package_manager
+ */
+class FakeSiteFixtureTest extends PackageManagerKernelTestBase {
+
+  /**
+   * Tests the complete stage life cycle using the 'fake-site' fixture.
+   */
+  public function testLifeCycle(): void {
+    $this->assertStatusCheckResults([]);
+    $this->assertResults([]);
+    // Ensure there are no validation errors after the stage lifecycle has been
+    // completed.
+    $this->assertStatusCheckResults([]);
+  }
+
+}