test_osds: remove scenario leftover
test_osds: remove scenario leftover

Since there's only only scenario available we don't need lvm_scenario
and no_lvm_scenario.
Also add missing assert for ceph-volume tests.

Signed-off-by: Dimitri Savineau <a50a620e679eed14f4e99998b821cea8884cf228@redhat.com>

ceph/ceph-ansible,ceph/ceph-ansible