Principal charm labels missing from logs

[cbartz]

Enhancement Proposal

We are using the grafana-agent (rev 108 & 166) with the github-runner-operator. For troubleshooting it would be useful if we could filter the logs by the application name of the principal charm. Currently juju_application and juju_unit always refer to the grafana-agent.

This means that to troubleshoot a particular unit, we always have to remap the principal unit name to the grafana-agent unit name.

I think this worked before #47 landed.