prometheus-operator-app release v0.11.0

Changed

• Sync with upstream chart version kube-prometheus-stack-19.3.0
  • Upgrade prometheus-operator from 0.49.0 to 0.50.0
  • fix .Values.grafana.sidecar.dashboards.multicluster
  • remove values.schema.json
  • fix docker image repositories
  • remove kube-webhook-certgen image sha