mgr, numpy and sub-interpreters

All, We have two issues: * https://tracker.ceph.com/issues/45574 * https://tracker.ceph.com/issues/48787 Caused by numpy not supporting Python sub-interpreters. Unfortunately, the latter issue came up in the most recent Octopus validations. I suspect it's just a matter of time, till our users are affected by it. Note that removing numpy is not easy, as kuberenetes-client depends (transitively) on numpy. Thoughts? - Sebastan