[base-cluster/grafana]: disable/upgrade old grafana angular dashboards

[tasches]

There are several dashboards in our grafana which are marked as deprecated. We should remove, upgrade or replace them

[marvinWolff]

The following dashboards contain angular components:

• cert-manager
• kubernetes-addons-velero-stats
• logging-dashboard-via-loki
• nginx-ingress-controller
• prometheus-overview

According to Grafana there is an automatic migration present, we need to test if the panels will still work after that.

If that is not the case we need to look for alternatives, or remove the panels.