Add OAuth/OpenID profile filter

With the newly added OAuth and OpenID drivers, it's possible to automatically create the user if they don't exist in the platform yet. However, this is currently an all-or-nothing setup. Useful for private user directories, like auth0 or Okta, but less ideal for big open platforms like Facebook or Google.

We should add a AUTH_<PROVIDER>_PUBLIC_REGISTRATION_FILTER that takes in [a filter rules object]( to allow for specific external providers to have access. This could be something like



or