Enable network policies in grafana, loki and prometheus

Enable network policies for contracts isolation.

https://jira.corp.caascad.com/browse/PF-2687

Depends on:

• caascad/applications/caascad-grafana!43 (merged)
• caascad/applications/caascad-loki!53 (merged)
• caascad/applications/caascad-kube-prometheus-stack!43 (merged)