fix(helm): update chart grafana to 6.59.5 (#2927)

| datasource | package | from   | to     |
| ---------- | ------- | ------ | ------ |
| helm       | grafana | 6.59.4 | 6.59.5 |

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

cluster/apps/monitoring/grafana/helm-release.yaml

@@ -9,7 +9,7 @@ spec:
   chart:
     spec:
       chart: grafana
-      version: 6.59.4
+      version: 6.59.5
       sourceRef:
         kind: HelmRepository
         name: grafana-charts