12 files declare their use of UpdatePathTestTrait in Drupal 9

ActiveWorkspaceUpdateTest.php in core/modules/workspaces/tests/src/Functional/UpdateSystem/ActiveWorkspaceUpdateTest.php

BrokenCacheUpdateTest.php in core/modules/system/tests/src/Functional/UpdateSystem/BrokenCacheUpdateTest.php

DatabaseVersionCheckUpdateTest.php in core/modules/system/tests/src/Functional/Update/DatabaseVersionCheckUpdateTest.php

EntityUpdateInitialTest.php in core/modules/system/tests/src/Functional/UpdateSystem/EntityUpdateInitialTest.php

UpdatePathLastRemovedTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePathLastRemovedTest.php

UpdatePathNewDependencyTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePathNewDependencyTest.php

UpdatePathTestBase.php in core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php

UpdatePathTestJavaScriptTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePathTestJavaScriptTest.php

UpdatePathWithBrokenRoutingTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePathWithBrokenRoutingTest.php

UpdatePostUpdateFailingTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePostUpdateFailingTest.php

UpdatePostUpdateTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePostUpdateTest.php

UpdateRemovedPostUpdateTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdateRemovedPostUpdateTest.php