feat: Self-Hosting: Add Support for SSO

[bbreunig]

Is your feature request related to a problem? Please describe.

I want to be able to log in with my SSO provider aside from Github, however I can only either use github or I have to create seperate Users

Describe the solution you'd like to see

I would like to see SSO support similar to grafana

Describe alternate solutions

I tried to misuse the GitHub Env-Variables to just add the secrets of my SSO Provider, however the login page redirects me to GitHub.

Additional information

No response