CI: UI improvements

This should not change the overall time, but allows for a nicer
UI when looking at the pipelines:

* first "check" icon is the container_prep stage
* second icon is all of the variations of builds
* third is the full test suite in the VM
* forth is the distribution specifics
* last one is the deploy

This allows to see which step fails from the UI instead of having
a lengthy list of jobs all in the same column.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
(cherry picked from commit 44b5fea1)