Issue #3304731 by phenaproxima, bnjmnm: Update remaining tests using Classy to use Starterkit

...src/FunctionalJavascript/FormErrorHandlerCKEditorTest.php

...ditor/tests/src/FunctionalJavascript/MediaLibraryTest.php

...les/ckeditor/tests/src/FunctionalJavascript/MediaTest.php

...itor5/tests/src/FunctionalJavascript/MediaLibraryTest.php

...es/ckeditor5/tests/src/FunctionalJavascript/MediaTest.php

core/modules/comment/tests/src/Functional/CommentCSSTest.php

core/modules/forum/tests/src/Functional/ForumTest.php

...s/language/tests/src/Functional/LanguageSwitchingTest.php

..._builder/tests/src/Functional/LayoutBuilderAccessTest.php

...layout_builder/tests/src/Functional/LayoutBuilderTest.php

...ests/src/Functional/LayoutBuilderThemeSuggestionsTest.php

...layout_builder/tests/src/Functional/LayoutSectionTest.php

..._builder/tests/src/FunctionalJavascript/AjaxBlockTest.php

.../tests/src/FunctionalJavascript/BlockFormMessagesTest.php

...sts/src/FunctionalJavascript/ContentPreviewToggleTest.php

...er/tests/src/FunctionalJavascript/ContextualLinksTest.php

...builder/tests/src/FunctionalJavascript/FieldBlockTest.php

.../src/FunctionalJavascript/InlineBlockPrivateFilesTest.php

...uilder/tests/src/FunctionalJavascript/InlineBlockTest.php

...tionalJavascript/LayoutBuilderDisableInteractionsTest.php