Authentification info is not stored properly

[gromdimon]

There are various problems with current authentification.

account_email field is not updated in db (table oauth_account)

Describe the bug
When user clicks verification link in the mail it follows this path:

1. Link https://reev.cubi.bihealth.org/verify-email?token=xxx
2. VerifyEmailView in frontend
3. sendVerifyRequest in AuthCline api
4. /internal/auth/verify endpoint in backend (refers to fastapi_users.get_verify_router(UserRead))
5. idk what happens later, but the db value of account_email field is not updated (table oauth_account)

Expected behavior
The account_email field should be changed.

Additional context
FastAPI-users discussions:
fastapi-users/fastapi-users#1359
fastapi-users/fastapi-users#1360

[gromdimon]

The related question to this issues should be raised as discussuion in fastapi-users as well