[cli-ref] Update python-manilaclient to 1.15.0
[cli-ref] Update python-manilaclient to 1.15.0

Change-Id: I5c58b35fa95a0d972fb7d050b462cf3377fa4590

openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals