mgr/volumes: Filter inherited snapshots while listing snapshots

mgr/volumes: Filter inherited snapshots while listing snapshots

Filter inherited snapshots resulted as part of a snapshot
at ancestor level while listing snapshots of a subvolume
and subvolumegroup

Also, fail the snapshot info on inherited snapshot.

Fixes: https://tracker.ceph.com/issues/48501
Signed-off-by: Kotresh HR <khiremat@redhat.com>
(cherry picked from commit bd49b6409be79dba4a119c809983a05687242732)

Conflicts:
    qa/tasks/cephfs/test_volumes.py: Few of the tests are re-organized,
      hence the conflicts. Resolved the same.