Expected behaviour

When using a custom authorization server, with OktaOpenIdConnect, the proper openid-configuration URL should be generated.

Actual behaviour

Okta OpenID Connect has two different URLs for the openid-configuration API.

• https://${yourOktaDomain}/.well-known/openid-configuration
• https://${yourOktaDomain}/oauth2/${authorizationServerId}/.well-known/openid-configuration

When using a authorization server the URL generation code truncates off the oauth2/${authorizationServerId} resulting in a 404 error when attempting to hit the openid-configuration URL. For the non-custom authorization server use case, the code works fine.

What are the steps to reproduce this issue?

1. Setup a custom authorization server in Okta for OpenID Connect
2. Set the SOCIAL_AUTH_OKTA_OPENIDCONNECT_API_URL variable to your custom server URL
3. Attempt to authenticate through the app.

Any logs, error output, etc?

I'm using this module through https://github.com/netbox-community/netbox which is currently pinned to version 4.1.0. The behavior I describe in this ticket is actually the opposite, custom-auth servers work and non-custom auth servers break. I wrote this issued based on this commit which sets up the behavior described in this issue.