Dockerfile doesn't have a HEALTHCHECK

Description

I looked at adding a HEALTHCHECK to the gitlab-runner Dockerfile using the gitlab-runner status command. However in my testing it would show only gitlab-runner: Service is not running.. I was able to get something useful with verify, but only if I added the runner name.

# gitlab-runner verify -n a710e8066e45
Runtime platform                                    arch=amd64 os=linux pid=499 revision=3afdaba6 version=11.5.0
Running in system-mode.                            
                                                   
Verifying runner... is alive                        runner=b297635a

I think automating this would require a script.

Proposal

I think a better way would be to make gitlab-runner status more Docker friendly, or add a new command gitlab-runner healthcheck that would verify the runner is up, and connected to the GitLab server.