Description of problem:

Login with GitHub with a DH 1.2 valid configuration in DH 1.3 fails with:
```
Login failed; caused by Error: Sign in failed: User not found in the RHDH software catalog. Verify that users/groups are synchronized to the software catalog. For non-production environments, manually provision the user or disable the user provisioning requirement. Refer to the RHDH Authentication documentation for further details.
```

1. The docs don't mention the required migration steps
2. The docs don't seem to have a valid config example in https://docs.redhat.com/en/documentation/red_hat_developer_hub/1.3/html/authentication/assembly-auth-provider-github
3. Could we consider having the error providing a direct link to the docs

Prerequisites (if any, like setup, operators/versions):

Steps to Reproduce

See attached configmap and backstage manifests.

Actual results:

Can't login

Expected results:

User gets logged in

Reproducibility (Always/Intermittent/Only Once):

Always

Build Details:

Additional info (Such as Logs, Screenshots, etc):