manila: install Jenkins built Ceph packages
manila: install Jenkins built Ceph packages

For manila-CephFS CI, latest Jewel Ceph packages built using
gitbuilder were installed. Jenkins based Ceph build system is going to
replace the gitbuilder based build system. Switch to using packages
built by the newer system.

Change-Id: Ic9b76bc5754dc8b98a11da9fadbeb9d6ace87d5b
Closes-bug: #1642678

openstack/devstack-plugin-ceph,ajarr/devstack-plugin-ceph