Issue #2281539 by ultimike, benjy | brockfanning: Fixed D6->D8 Profile field (list selection).

...onfig/install/migrate.migration.d6_user_profile_field.yml

...rate_drupal/src/Plugin/migrate/source/d6/ProfileField.php

...rupal/src/Plugin/migrate/source/d6/ProfileFieldValues.php

core/modules/migrate_drupal/src/Tests/Dump/Drupal6User.php

.../migrate_drupal/src/Tests/d6/MigrateProfileValuesTest.php

...upal/src/Tests/d6/MigrateUserProfileEntityDisplayTest.php

.../src/Tests/d6/MigrateUserProfileEntityFormDisplayTest.php

...upal/src/Tests/d6/MigrateUserProfileFieldInstanceTest.php

...grate_drupal/src/Tests/d6/MigrateUserProfileFieldTest.php

...s/migrate_drupal/tests/src/source/d6/ProfileFieldTest.php