Bind metrics in prometheus format to Kubernetes Monitoring system

Goal

use metrics from prometheus or thanos to analyze the service and also in the futur set alerts based on theses metrics.

Technical details

Service URI: /api/v1/metrics should be mapped to /metrics from a pod perspective because it is the endpoint that will fetch Kubernetes by default to get the metrics of the service.

something already exist and can be setup as dependency to handle that : https://github.com/apache/geronimo-metrics

helm chart

define/override default configuration in the helm chart to follow Talend helm recommendation (specific /metrics path at the pod level and a specific port).

something like http://localhost:9000/metrics 

the service monitor has been already setup in the helm chart (related PR)