* CI: reduce VM resources requests to improve scheduling
* CI: Reduce default jobs; add labels(ci-full/extended) to run more test
* CI: use jobs dependencies instead of stages
* precommit one-job
* CI: Use Kubevirt VM to run Molecule and Vagrant jobs
Use gitlab dynamic child pipelines feature to have one source of truth
for the pre-commit jobs, the pre-commit config file.
Use one cache per pre-commit. This should reduce the "fetching cache"
time steps in gitlab-ci, since each job will have a separate cache with
only its hook installed.