Update Helm release grafana to v8.11.2

Author: renovate[bot]

monitoring/argo-apps/grafana.yaml

@@ -13,7 +13,7 @@ spec:
       directory:
         recurse: true
     - repoURL: https://grafana.github.io/helm-charts
-      targetRevision: 8.10.0
+      targetRevision: 8.11.2
       chart: grafana
       helm:
         valueFiles: