Velero ServiceMonitor enabled in BigBang

The Velero chart provides a serviceMonitor template which is enabled via metrics.serviceMonitor.enabled

Add a passthrough value in chart/templates/velero/values.yaml that will conditionally enable that value based on the enabled status of the monitoring package (similar to the monitoring.enabled key already in the velero passthrough values). Velero has some documentation available for troubleshooting the metrics endpoint: https://velero.io/docs/v1.8/troubleshooting/#velero-is-not-publishing-prometheus-metrics

• ServiceMonitor enabled passthrough value added
• Metrics endpoint showing up in Prometheus as healthy
• Metrics endpoint returning prometheus metrics