adjusted authad language files for config option change

lib/plugins/authad/auth.php

lib/plugins/authad/lang/bg/settings.php

lib/plugins/authad/lang/de-informal/settings.php

lib/plugins/authad/lang/de/settings.php

lib/plugins/authad/lang/en/settings.php

lib/plugins/authad/lang/eo/settings.php

lib/plugins/authad/lang/fr/settings.php

lib/plugins/authad/lang/ko/settings.php

lib/plugins/authad/lang/nl/settings.php

lib/plugins/authad/lang/pt-br/settings.php

lib/plugins/authad/lang/zh-tw/settings.php

lib/plugins/authad/lang/zh/settings.php