remove custom controler for user provided password auth

apps/files_external/appinfo/routes.php

apps/files_external/controller/usercredentialscontroller.php

...iles_external/controller/userglobalstoragescontroller.php

apps/files_external/js/settings.js

apps/files_external/lib/auth/iuserprovided.php

apps/files_external/lib/auth/password/userprovided.php

apps/files_external/lib/storageconfig.php