Issue #3192900 by quietone, Matroskeen: Combine some migration kernel tests

...omment/tests/src/Kernel/Migrate/d7/MigrateCommentTest.php

...c/Kernel/Migrate/d6/MigrateUserConfigsTranslationTest.php

.../Kernel/Migrate/d6/MigrateLanguageContentSettingsTest.php

...ules/node/tests/src/Kernel/Migrate/d7/MigrateNodeTest.php

.../path/tests/src/Kernel/Migrate/d6/MigrateUrlAliasTest.php

...y/tests/src/Kernel/Migrate/d6/MigrateTermNodeComplete.php

...y/tests/src/Kernel/Migrate/d7/MigrateTaxonomyTermTest.php

...er/tests/src/Kernel/Migrate/d6/MigrateUserConfigsTest.php

...ts/src/Kernel/Migrate/d6/MigrateUserPictureD6FileTest.php

...ules/user/tests/src/Kernel/Migrate/d7/MigrateUserTest.php