chore(deps): update azure/k8s-deploy action to v6 (#45)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [azure/k8s-deploy](https://github.com/azure/k8s-deploy) | action | major | `v5.1.0` → `v6.0.0` |

---

### Release Notes

<details>
<summary>azure/k8s-deploy (azure/k8s-deploy)</summary>

### [`v6.0.0`](https://github.com/Azure/k8s-deploy/releases/tag/v6.0.0)

[Compare Source](https://github.com/azure/k8s-deploy/compare/v5.1.0...v6.0.0)

##### Changed

- [#&#8203;504](https://github.com/azure/k8s-deploy/issues/504) [Update Node.js runtime from node20 to node24](https://github.com/Azure/k8s-deploy/pull/504)
- [#&#8203;500](https://github.com/azure/k8s-deploy/issues/500) [Update action version references in README to latest majors](https://github.com/Azure/k8s-deploy/pull/500)

##### Security

- [#&#8203;506](https://github.com/azure/k8s-deploy/issues/506) [Bump undici from 6.23.0 to 6.24.1](https://github.com/Azure/k8s-deploy/pull/506)
- [#&#8203;513](https://github.com/azure/k8s-deploy/issues/513) [Bump vite from 8.0.3 to 8.0.5](https://github.com/Azure/k8s-deploy/pull/513)
- [#&#8203;509](https://github.com/azure/k8s-deploy/issues/509) [Bump the actions group across 1 directory with 4 updates](https://github.com/Azure/k8s-deploy/pull/509)
- [#&#8203;510](https://github.com/azure/k8s-deploy/issues/510) [Bump the actions group across 1 directory with 2 updates](https://github.com/Azure/k8s-deploy/pull/510)
- [#&#8203;511](https://github.com/azure/k8s-deploy/issues/511) [Bump vitest from 4.1.1 to 4.1.2](https://github.com/Azure/k8s-deploy/pull/511)
- [#&#8203;514](https://github.com/azure/k8s-deploy/issues/514) [Bump the actions group with 2 updates](https://github.com/Azure/k8s-deploy/pull/514)
- [#&#8203;501](https://github.com/azure/k8s-deploy/issues/501) [Bump @&#8203;types/node from 25.3.3 to 25.4.0](https://github.com/Azure/k8s-deploy/pull/501)

</details>

---

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Reviewed-on: https://gitea.t000-n.de/t.behrendt/k_deploy_workflows/pulls/45
Reviewed-by: t.behrendt <t.behrendt@noreply.localhost>
Co-authored-by: Renovate Bot <renovate@t00n.de>
Co-committed-by: Renovate Bot <renovate@t00n.de>

.gitea/workflows/cd.yaml

@@ -104,7 +104,7 @@ jobs:
             echo "No custom secrets to create"
           fi
       - name: Deploy Kubernetes manifests
-        uses: azure/k8s-deploy@c8cfec839dc09896b3b8cc40cd13d04792680771 # v5.1.0
+        uses: azure/k8s-deploy@c7ebd0d5f39477a23f1b5dea0f52e6db04adf28e # v6.0.0
         with:
           action: deploy
           manifests: "${{ inputs.k8s_dir }}"