tf-stage2: remove RegistrationProfile form action

The form action RegistrationProfile has been removed in Keycloak 23.

Relevant information from the upgrading guide [1]:

> The validation of user attributes as well as creation of the user
> including all that user’s attributes is handled by
> RegistrationUserCreation form action and hence RegistrationProfile
> is not needed anymore.

[1] https://www.keycloak.org/docs/23.0.0/upgrading/#removed-registrationprofile-form-action



Co-authored-by: Kristian Klausen <kristian@klausen.dk>