Is your feature request related to a problem? Please describe.
Yes, currently Prometheus only scans for ServiceMonitors with the release: kube-prometheus-stack label, but it can't find the agones SeviceMonitors because the release label is hardcoded to the helm chart release of agones.

Describe the solution you'd like
I'd like to be able to configure that label and others via a parameter called agones.metrics.serviceMonitor.labels that accepts a map.

Describe alternatives you've considered
If the label isn't provided, we could also just default back to the agones helm chart release

Additional context
I can get this done if you'd like.

Here's some context:
prometheus-operator/kube-prometheus#1392 (comment)

Link to the Agones Feature Proposal (if any)
The link to the AFP PR.

Discussion Link (if any)