Zuul v3: Use mirrored git repos in base job
This replaces our current rsync with a series of git push operations
using the repo mirrors baked into our images.  This has been tested
with the devstack-legacy job and appears to work.
- hosts: all
roles:
- add-build-sshkey
- - prepare-workspace
+ - start-zuul-console
+ - use-cached-repos
+ - mirror-workspace-git-repos
- role: validate-host
# TODO(mordred) When we have site-local variables, these should go there
zuul_traceroute_host: git.openstack.org
