Support private GitLab repositories

Hi There

After a lot of trawling the internet I am fairly sure that SourceLink does not support private GitLab repositories. Based on my reading I think this is because GitCrendentialManager will only use Basic Authentication, and GitLab will not accept Basic Authentication.

Firstly, can someone confirm that this is the case?

Secondly, is there a plan to fix this? SourceLink is near useless to us unless we can use it with private repositores. My initial thought is that its not acceptable to ask GitLab to support Basic Authentication, being as it is basically a bad idea.

Thanks

Cedd