chore(deps): update grafana/grafana docker tag to v12.4.3 (#621)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [grafana/grafana](https://redirect.github.com/grafana/grafana) | patch
| `12.4.2` → `12.4.3` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the [Dependency
Dashboard](../issues/4) for more information.

---

### Release Notes

<details>
<summary>grafana/grafana (grafana/grafana)</summary>

###
[`v12.4.3`](https://redirect.github.com/grafana/grafana/blob/HEAD/CHANGELOG.md#1243-2026-04-14)

[Compare
Source](https://redirect.github.com/grafana/grafana/compare/v12.4.2...v12.4.3)

##### Features and enhancements

- **Analytics:** Keep internal dashboard id
[#&#8203;121417](https://redirect.github.com/grafana/grafana/pull/121417),
[@&#8203;ryantxu](https://redirect.github.com/ryantxu)
- **Go:** Update to 1.25.9
[#&#8203;122095](https://redirect.github.com/grafana/grafana/pull/122095),
[@&#8203;macabu](https://redirect.github.com/macabu)
- **Reporting:** Correctly apply appSubURL to report settings requests
(Enterprise)

##### Bug fixes

- **Alerting:** Document Grafana HA Alertmanager cluster metrics prefix
change in Grafana 12.4
[#&#8203;121481](https://redirect.github.com/grafana/grafana/pull/121481),
[@&#8203;alexander-akhmetov](https://redirect.github.com/alexander-akhmetov)

<!-- 12.4.3 END -->

<!-- 13.0.0 START -->

</details>

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Author: bootjp

monitoring/docker-compose.yml

@@ -12,7 +12,7 @@ services:
       - "host.docker.internal:host-gateway"
 
   grafana:
-    image: grafana/grafana:12.4.2
+    image: grafana/grafana:12.4.3
     depends_on:
       - prometheus
     ports: