Disable push to quay.io
Disable push to quay.io

This change disables any push attempt to quay.io, it has proven to be
unstable with our pushes, doubles the time to complete a promotion, and
any single failure blocks the progress on a single promotion.
We can reenable it in the future after at least:
- multi arch manifest will be enabled.
- we have debugged the causes of push failure with quay team.
- (suggesting) we have a way to parallelize push to different target
registries.

Change-Id: I1a28664779dd91a9bdd1b32dfc3d7977896c1949

redhat-openstack/rdo-infra,rdo-infra/ci-config,rdo-infra/ci-config,redhat-openstack/rdo-infra,redhat-openstack/rdo-infra,redhat-openstack/rdo-infra,rdo-infra/ci-config,rdo-infra/ci-config