As part of  this removes the unneeded zuul layout overrides.
All the jobs removed here are already included with the relevant
templates. The files: matches that were used for the scenario
standalones are moved to the template layout via the depends-on.
The build-containers-ubi8 job is not needed as it is exercised
by the content providers and we have removed this job from other
(cherry picked from commit 22e5366de1)