This should ensure that if we have a parent job that updates the gitea
version and a do not merge child job that induces an artificial failure
for zuul hold purposes that we test the correct image in the child job's
changes.
Prior to this we were testing the existing published images, but
provides + requires will give the correct signaling to make the desired
"test new proposed image" behavior happen in the child change builds.
Change-Id: Ie6b827b650e0f32606dc5ec7f4aa0adfeebdeb5e
c2d46f4247