Configurable gitlab host

[LLukas22]

Please describe the feature you want

It would be a nice addition if the GitLab host were configurable, to easily point the Tabby server to a self-hosted GitLab instance.

Additional context

Since it is unlikely that a single Tabby instance needs to access both a self-hosted and the public GitLab instance, it would probably be enough to make the host configurable via, for example, a GITLAB_HOST environment variable and simply query the value when the GitlabBuilder is created here.

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Please reply with a 👍 if you want this feature.

[boxbeam]

This is planned! The feature will most likely be rolling out with the next release (0.12).