Add example how to work when you are not allowed to create namespaces on the Hub

[ch-stark]

let's assume only the Cluster-Admin can create namespaces on the Hub.
What does this mean for developers who want to deploy applications and clusterset-admins which want to create clusters.
For developers there might be the option to use decentralized argocd

[ch-stark]

decentralized argocd: this translates to tenant configuration managed by the openshift-gitops instance on the Managed-Cluster itself

[ch-stark]

For ApplicationSets the ClusterAdmin can generate the namespaces beforehand
We need to consider: https://argo-cd.readthedocs.io/en/stable/operator-manual/applicationset/Security/