Zuul: add file extension to playbook path
Zuul: add file extension to playbook path

Zuul now supports including the file extension on the playbook path
and omitting the extension is now deprecrated.  Update references
to include the extension.

Change-Id: Iff8fe66e0a7825ed7a6b0cecfdc1cd30bb0bde75

openstack/zaqar,openstack/zaqar,openstack/zaqar,openstack/zaqar