feat(helm)!: Update chart kube-prometheus-stack to 56.21.2

| datasource | package               | from   | to      |
| ---------- | --------------------- | ------ | ------- |
| helm       | kube-prometheus-stack | 54.2.2 | 56.21.2 |

cluster/apps/monitoring/kube-prometheus-stack/app/helmrelease.yaml

@@ -9,7 +9,7 @@ spec:
   chart:
     spec:
       chart: kube-prometheus-stack
-      version: 54.2.2
+      version: 56.21.2
       sourceRef:
         kind: HelmRepository
         name: prometheus-community