Review [1] handles symlinking of python Ceph libraries outside of venv.
This commit simply removes installing python-cephlibs.
[1] https://review.openstack.org/#/c/317901/
Backport of https://review.openstack.org/#/c/319972/
Change-Id: I5f88fc59da8b634849d01fbea005be7f50dcf0be
Depends-On: Ib26c84f6671523b40e61f043713db58d8a756dc9
(cherry picked from commit 7e6fa1cd64)