Add github sync job for tricircle
Add github sync job for tricircle

To sync the retirement change, we need add the github mirroring, add
the usual template.

This is important so that on github the retirement README is shown.

Change-Id: Ib2ebe108cba1e26b4cb89b6fe072d719a183d941

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