The active releases according to [1] are octopus and nautlius. Remove
the old releases from our mirroring. This needs manual cleanup of the
jobs and volumes -- I will do this manually as this is mostly about
clearing out old things before moving the mirroring to Ansible.
[1] https://docs.ceph.com/en/latest/releases/
Change-Id: I050f737521fa6837f3b6b52b8028a839a29f7bd2
961bab63d9
