Description of the problem, including code/CLI snippet

Rebase operation (via gitlab) is asynchronous so if for example you want to do merge afterwards there is no way if rebase is finished or not.

mr.rebase ()
# somehow wait for rebase🤔
mr.merge ()

Expected Behavior

Possibility to check if rebase is in progress which is supported by gitlab api (see include_rebase_in_progress in https://docs.gitlab.com/ee/api/merge_requests.html)

Actual Behavior

No way to check rebase in progress, having to rely on crude timers and so on.

I can see that in #823 it was specially left out but would it possible to support it maybe via separate function which does a request again and returns only this field maybe?

The other way is support rebase & merge operation as one but it might be not very flexible approach since error may happen during rebase &c.