feat(helm): update chart grafana to 8.6.0 (#1082)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [grafana](https://grafana.com)
([source](https://redirect.github.com/grafana/helm-charts)) | minor |
`8.5.12` -> `8.6.0` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
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---

### Release Notes

<details>
<summary>grafana/helm-charts (grafana)</summary>

###
[`v8.6.0`](https://redirect.github.com/grafana/helm-charts/releases/tag/grafana-8.6.0)

[Compare
Source](https://redirect.github.com/grafana/helm-charts/compare/grafana-8.5.12...grafana-8.6.0)

The leading tool for querying and visualizing time series and metrics.

#### What's Changed

- \[grafana] Implement Gateway API by
[@&#8203;jkroepke](https://redirect.github.com/jkroepke) in
[https://github.com/grafana/helm-charts/pull/3400](https://redirect.github.com/grafana/helm-charts/pull/3400)

**Full Changelog**:
grafana/helm-charts@tempo-vulture-0.7.0...grafana-8.6.0

</details>

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kubernetes/apps/monitoring/grafana/app/helmrelease.yaml

@@ -10,7 +10,7 @@ spec:
   chart:
     spec:
       chart: grafana
-      version: 8.5.12
+      version: 8.6.0
       sourceRef:
         kind: HelmRepository
         name: grafana-charts