@coqbot could report failures from GitLab CI and restart spurious ones about bot

[Zimmi48]

This is going to be way easier than I thought thanks to the job webhook, the build trace API endpoint and the build retry API endpoint (cf. bf62f4b and https://docs.gitlab.com/ee/api/jobs.html#retry-a-job).

[Zimmi48]

This is basically implemented now and further enhancements can be treated in separate issues.

[ejgallego]

Thanks for this great work.

[Zimmi48]

Actually something is missing from the webhook load or the trace to be able to tell whether the failure is due to a failing runner. Cf. https://gitlab.com/gitlab-org/gitlab-ee/issues/6408

[Zimmi48]

Another unrelated problem to put this in practice would be to stop relying on Heroku's free dynos as GitLab job webhook generates way too many requests to let the bot have the 7 hours of statutory sleep.

[ejgallego]

Please disable the report functionality until the "stale build problem" is fixed as detailed in coq/coq#7871 (comment)

[Zimmi48]

OK, this is fixed now.

[ejgallego]

Thanks!!!