vexxhost: add openstack/openstack-zuul-jobs
There are a few roles which are used by devstack which are in
that repository so we need to add it.
- openstack/keystone
- openstack/neutron
- openstack/nova
+ - openstack/openstack-zuul-jobs
- openstack/oslo.cache
- openstack/oslo.concurrency
- openstack/oslo.config
