OCI method missing in CSPO docs

[Nils98Ar]

These OCI parts need to be added to the CSPO docs as well:

• https://docs.scs.community/docs/container/components/cluster-stacks/components/cluster-stack-operator/topics/quickstart#using-oci-registry
• https://docs.scs.community/docs/container/components/cluster-stacks/components/cluster-stack-operator/topics/quickstart#enable-oci-registry-as-source with -n cspo-system cspo-controller-manager instead of -n cso-system cso-controller-manager in the kubectl patch command.

And propably a general information that both Github and OCI are possible similar to what is written here: https://docs.scs.community/docs/container/components/cluster-stacks/components/cluster-stack-operator/topics/quickstart#configure-release-source.

I think this should usually be added to the Cluster Stack Provider OpenStack Quickstart but this one refers to the Predefined Cluster Stacks OpenStack Quickstart where it probably doesn't fit.