[Development] The containers in the "containers" branch

[Rohan McGovern]

Oswald Buddenhagen said:
> 
> > For future reference, whoever is bypassing the CI to change the SHA1 of
> > a branch should also issue a command like this to update the staging
> > branch:
> > 
> >   ssh -p 29418 codereview.qt-project.org gerrit staging-rebuild --project qt/qtbase --branch containers
> > 
> > , which I have now done, fixing the conflict.
> >
> that's slight overkill. when you direct-push to a branch with no
> activity, you can just direct-push the staging branch as well - you just
> edit the command line, replacing heads with staging.

Doing the staging-rebuild command would correctly take into account any
changes which are currently staged (if any).  If you do a force push to
the staging branch, changes could be left in 'staged' state in the
database but not actually be present in the staging branch.