Introduce Monitor support for CSR resource

Introduce Monitor support for CSR resource

These changes allow the Monitor to also track CSR
(CertificateSigningResource) resources which will make
it possible to know when a certificate has been issued by
the K8s cluster signer. In turn, DCM will be able to read,
store and use that certificate to generate kubeconfigs.

Out-of-tree actions required:
- publish monitor's docker image built from this source
  onto emcov2/monitor:latest

Issue-ID: MULTICLOUD-1143
Change-Id: I7facd27bbfe08891151bb3b6a9a19948435e24e4
Signed-off-by: Igor D.C <igor.duarte.cardoso@intel.com>