Describe the bug
Only the defaults value of OIDC_SERVER_CLASS is being used when in the case of the fallback of no setting for OAUTH2_SERVER_CLASS when OIDC_ENABLED
To Reproduce
If the user hasn't overridden OAUTH2_SERVER_CLASS and they are setting OIDC_ENABLED to True, and they have overridden OIDC_SERVER_CLASS, then only the defaults value of OIDC_SERVER_CLASS is used, instead of the overridden value.
Expected behavior
The user setting of OIDC_SERVER_CLASS should be used, and if not set, fallback to the value in the defaults.
Version
2.3.0 but it's also present in 3.1.0
Additional context