Enable Prometheus metrics without ServiceMonitor

[prashcr]

Is your feature request related to a problem?
I want to enable Prometheus metrics from aws-load-balancer-controller without creating a ServiceMonitor and having Prometheus Operator on my EKS cluster. This is because I'm using an alternative Prometheus collector: Grafana Agent.

Currently the Helm chart defines a single serviceMonitor.enabled variable to enable both the Prometheus metrics service and the ServiceMonitor.

Is your feature request related to a specific Helm chart, if yes mention name of the chart?
My primary concern is aws-load-balancer-controller though this applies to all charts that expose a Prometheus metrics endpoint (e.g. aws-node-termination-handler, aws-for-fluent-bit)

Describe the solution you'd like
The Helm charts defines a new metrics.enabled variable. The metrics Service is created if metrics.enabled OR serviceMonitor.enabled

Describe alternatives you've considered
None.

[prashcr]

I just realized this chart is a mirror of https://github.com/kubernetes-sigs/aws-load-balancer-controller so I duplicated the issue and PR there.
kubernetes-sigs/aws-load-balancer-controller#3244
kubernetes-sigs/aws-load-balancer-controller#3245