pybind/ceph_volume_client: Preserve existing caps while authorize/deauthorize auth-id

pybind/ceph_volume_client: Preserve existing caps while authorize/deauthorize auth-id

Authorize/Deauthorize used to overwrite the caps of auth-id which would
end up deleting existing caps. This patch fixes the same by retaining
the existing caps by appending or deleting the new caps as needed.

Fixes: https://tracker.ceph.com/issues/48555
Signed-off-by: Kotresh HR <khiremat@redhat.com>
(cherry picked from commit 47100e528ef77e7e82dc9877424243dc6a7e7533)

Origin: upstream, https://github.com/ceph/ceph/commit/eb2fa6934fc736f8abe6d9e237b0a14c9d877626

Gbp-Pq: Name CVE-2020-27781-3.patch