Pierre-Yves David <pierre-yves.david@octobus.net> [Wed, 28 Jun 2017 18:18:59 +0200] rev 2674
topic: adjust head checking wrapping to not interfere with concurrent push
In the previous form, the new topic head was detected as affected and the push
was rejected.
We introduce a of 'test-topic-push.t' using the new race checker as there have
been many compatibility issue with this new checkers.