gitlab-ci: be bold and try to run the full test in them

This is a basic version that should work reasonably well. The setup is a bit
costly and the cleanup is not guaranteed yet.

--HG--
branch : stable
2 jobs for topic/stable/ci-more in 11 minutes and 47 seconds (queued for 3 seconds)
Status Name Job ID Coverage
  Test
passed flake8 #29119

00:00:13

passed tests #29120

00:11:47