Support for configuring prometheus metrics collector

[jompu]

CloudWatch Agent already supports this: https://github.com/aws/amazon-cloudwatch-agent/blob/main/translator/config/schema.json#L757C13-L758C27

It should be possible to give the prometheus configuration for agent to use instead of the file pointed by "prometheus_config_path" property.

Currently one needs to deploy another CloudWatch agent just to collect Prometheus metrics.

[lisguo]

There is a current feature gap with the amazon-cloudwatch-observability helm chart with prometheus. We are aware of the issue and are discussing it internally.

In the meantime if you wanted prometheus metrics you would have to use something like this: https://github.com/aws-samples/amazon-cloudwatch-container-insights/tree/536ba3dd2b8af060182fad4e5972568b2ee9452c/k8s-deployment-manifest-templates/deployment-mode/service/cwagent-prometheus