Update Helm release grafana to v8.8.2 (#1269)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

kustomize/bases/grafana/kustomization.yaml

@@ -5,7 +5,7 @@ namespace: observability
 helmCharts:
   - name: grafana
     repo: https://grafana.github.io/helm-charts
-    version: 8.6.4
+    version: 8.8.2
     releaseName: grafana
     namespace: observability
     valuesFile: helm-values.yaml