Add new state ceph.create_pool.req.sent to gate sending the ceph
pool creation request. This fixes a problem where the changed
method in requires of ceph-client interface raises the
'{relation_name}.pools.available' state but the create_pool
method then removes it again.
Also remove snap functional tests as they are no longer
needed since that install method via charms is not
actively supported.
Change-Id: Iaf986d24f005bcc7c8f485cfc2eb1775e6dbbbdd
Closes-Bug: #1846480
d0d2ac8864