Issue #3462529 by catch: Mark more tests with @group #slow and remove it from some others

.../comment/tests/src/Functional/Rest/CommentXmlAnonTest.php

...ent/tests/src/Functional/Rest/CommentXmlBasicAuthTest.php

...omment/tests/src/Functional/Rest/CommentXmlCookieTest.php

...tests/src/Functional/Formatter/FileAudioFormatterTest.php

...tests/src/Functional/Formatter/FileVideoFormatterTest.php

...odules/user/tests/src/Functional/Rest/UserXmlAnonTest.php

...s/user/tests/src/Functional/Rest/UserXmlBasicAuthTest.php

...ules/user/tests/src/Functional/Rest/UserXmlCookieTest.php

core/modules/user/tests/src/Functional/UserCancelTest.php

...dules/user/tests/src/Functional/UserPasswordResetTest.php

...odules/user/tests/src/Functional/UserRegistrationTest.php

core/modules/views_ui/tests/src/Functional/FilterUITest.php