docs(security): update Azure OAuth2 config to use /v2.0/ endpoint

[sfirke]

Description

I had used the existing Azure OAuth config from this repo for several years in my Superset instance. Now our Azure Entra is requiring multi-factor authentication and we could not find a way to force MFA with that config.

The solution was to move to the v2.0 endpoint, which has been available for at least six years. Many GitHub posts, gists, StackOverflow posts show people using this newer config for Airflow and Superset. E.g., this popular gist.

This has been tested on my Superset including that mapping of AD group to Superset roles works. Users still get assigned roles correctly if that is configured following the FAB docs.

I also updated the toy Azure config in the OAuth examples file, for good measure. Note: I misunderstood this file in an earlier version of the PR - I've edited this description and force-pushed updated code upon properly understanding and using that example.

ADDITIONAL INFORMATION

• Has associated issue:
• Is CRUD MVC related.
• Is Auth, RBAC security related.
• Changes the security db schema.
• Introduces new feature
• Removes existing feature