On prem private Gitlab repositores support with OAuth2 flow (without Keycloak)

[skabashnyuk]

Is your task related to a problem? Please describe

Today Gitlab private factories that are required OAuth2 authorization are redirected to keycloak.
However, in devworkspaces keycloak is no longer a mandatory infrastructure element.

Describe the solution you'd like

OAuth2 configuration should be mounted as a file #20496.
Embedded OAuth2 integration should be configured and used.

Describe alternatives you've considered

No response

Additional context

• Private Github factories with OAuth2 providers without keycloak #20497
• Fixup for oauth2 usernames che-server#185

Release notes text

Workspaces started using the DevWorkspace engine now support on premise private Gitlab repositories. On premise private Bitbucket and github.com private repositories were already supported.

[benoitf]

moving issue to 7.42 milestone as this issue is part of the endgame

[l0rd]

@skabashnyuk can we close this issue or is there something to finish (like Gitlab SAAS support)?

[skabashnyuk]

I think we can close this. Gitlab SAAS most likely should be a different task. It was not in the scope of this one.

[devstudio-release]

sync'd to Red Hat JIRA https://issues.redhat.com/browse/CRW-2713