Merge branch 'CVE-2020-27781-luminous' into HEAD

Merge branch 'CVE-2020-27781-luminous' into HEAD

* CVE-2020-27781-luminous:
  tasks/cephfs/test_volume_client: Add tests for authorize/deauthorize
  pybind/ceph_volume_client: Optionally authorize existing auth-ids
  pybind/ceph_volume_client: Preserve existing caps while authorize/deauthorize auth-id
  pybind/ceph_volume_client: Disallow authorize auth_id
  pybind/ceph_volume_client: Fix PEP-8 SyntaxWarning

Reviewed-by: Ramana Raja <rraja@redhat.com>
Reviewed-by: Kotresh Hiremath Ravishankar <khiremat@redhat.com>