feat: allow to set the persistent log level per pod

[Wielewout]

This PR allows to control per pod the level for logs that should be persisted. The default is warning (mainly for third-party pods of drax or external pods like the kubernetes api server).

Note that I've set loki-gateway also to warning. We maintain the helm chart ourselves with the common chart templates, but it's running nginx.

TODO:

• [x] #788
• [x] Release new common chart (#791)
• [x] Let renovate bump the common chart for the others (#792)
• [x] Rebase this PR

[dimgogos]

Don't we need to set info level logs for our other microservices too? e.g. dashboard, service monitor, orchestrator ...?