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: I9335e07095ec7d2821441f70ce2a73d626bc2291

openstack/octavia,openstack/octavia,openstack/octavia