Update stalwartlabs/stalwart Docker tag to v0.14.1

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [postgres-cluster](https://github.com/cloudnative-pg/charts) ([source](https://github.com/cloudnative-pg/charts/tree/HEAD/charts/cluster)) | minor | `6.15.0` -> `6.16.0` |

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### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update again.

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 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

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This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: #2058
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/platform/stalwart/values.yaml

@@ -9,7 +9,7 @@ stalwart:
         main:
           image:
             repository: stalwartlabs/stalwart
-            tag: v0.13.4
+            tag: v0.14.1
             pullPolicy: IfNotPresent
           resources:
             requests:

clusters/cl01tl/services/harbor/Chart.yaml

@@ -21,7 +21,7 @@ dependencies:
     repository: https://helm.goharbor.io
   - name: postgres-cluster
     alias: postgres-17-cluster
-    version: 6.15.0
+    version: 6.16.0
     repository: http://gitea-http.gitea:3000/api/packages/alexlebens/helm
 icon: https://cdn.jsdelivr.net/gh/selfhst/icons/png/harbor.png
 appVersion: v2.13.0