Refactor cluster-wide content when feature goes GA

The cluster-wide deployment functionality was rolled out as a TP feature in 2.3. When the feature goes GA we should move the content from the release notes to the core docs.

We should also include a fuller concept topic, something similar this this, and add it to the SM deployment models section of the core docs

https://51715--docspreview.netlify.app/openshift-enterprise/latest/service_mesh/v2x/ossm-deployment-models.html