Drop references to prometheus monitors for Metrics Server

[rajatvig]

Checklist

• I have verified that my change is according to the deprecations & breaking changes policy
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• README is updated with new configuration values (if applicable) learn more
• A PR is opened to update KEDA core (repo) (if applicable, ie. when deployment manifests are modified)

Fixes

Removes monitoring code snippets for Keda Metrics Server

[JorTurFer]

Hi!
I think that we shouldn't remove these references because metrics server still exposes Prometheus metrics: https://keda.sh/docs/2.11/operate/prometheus/#metrics-server

Currently, it only exposes operator-sdk metrics, but maybe in the future we add more metrics again to the metrics server to improving the observability there.

WDYT @tomkerkhove @zroubalik ? Should we remove the references now and add them again when we expose more metrics throught metrics server?

[rajatvig]

@JorTurFer Had checked on the Metrics Server process. Nothing is bound to port 8080 on the process and as such there are no metrics.

[JorTurFer]

@JorTurFer Had checked on the Metrics Server process. Nothing is bound to port 8080 on the process and as such there are no metrics.

We should have an error in metrics server because the operator-sdk should expose them, maybe we have some mistake there, let me check it

[JorTurFer]

I can confirm that it's due to a bug. During this commit I removed the startup of the metrics server.
Definitively, I need to go deeper to know how to solve it, but the metrics server should expose the REST API metrics, so I'd not remove it.
@zroubalik @tomkerkhove ?