puppet: remove workaround for mitaka/hammer branches
puppet: remove workaround for mitaka/hammer branches

stable/hammer & stable/mitaka have been EOLed so we don't need these
workarounds anymore in JJB.

Change-Id: I9a9f89f9b7fb2366bb22cf24db3a659d4f6d4dcc

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