OSA: Prevent CentOS jobs executing for Newton and older
OSA: Prevent CentOS jobs executing for Newton and older

For the Newton and older branches of the openstack-ansible repo,
the CentOS jobs should not run.

Change-Id: I5ba3e4c7a1e73b3b3b5d57712c07a7eb28fb30db

openstack-infra/project-config,openstack-infra/project-config