[kube-prometheus-stack] Upgrade Grafana to 6.56.* (#3302)

Cause of https://grafana.com/blog/2023/04/26/grafana-security-release-new-versions-of-grafana-with-security-fixes-for-cve-2023-28119-and-cve-2023-1387/

Need to wait for grafana/helm-charts#2371

Signed-off-by: Sven Schliesing <muffl0n@raffts.net>

charts/kube-prometheus-stack/Chart.yaml

@@ -21,7 +21,7 @@ name: kube-prometheus-stack
 sources:
   - https://github.com/prometheus-community/helm-charts
   - https://github.com/prometheus-operator/kube-prometheus
-version: 45.23.0
+version: 45.24.0
 appVersion: v0.63.0
 kubeVersion: ">=1.16.0-0"
 home: https://github.com/prometheus-operator/kube-prometheus
@@ -48,6 +48,6 @@ dependencies:
     repository: https://prometheus-community.github.io/helm-charts
     condition: nodeExporter.enabled
   - name: grafana
-    version: "6.54.*"
+    version: "6.56.*"
     repository: https://grafana.github.io/helm-charts
     condition: grafana.enabled