[siibra] Ephemeral storage per namespace/ per pod

Grafana dashboard includes Ephemeral storage metrics

per namespace: Possible per pod: WIP

added Platform label

assigned to @vgeo

@xgui3783 FYI

We currently provide:

• The total and used ephemeral storage per namespace in the Siibra Workloads Metrics dashboard
• The limit and requested ephemeral storage per pod in the Siibra Pods Metrics dashboard

Still pending, the actual used ephemeral storage per pod.

Tracking continues here: https://gitlab.ebrains.eu/ri/tech-hub/devops/base/-/issues/259

closed