Update Helm release postgres-cluster to v6

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [ghcr.io/tautulli/tautulli](https://github.com/Tautulli/Tautulli) | minor | `v2.15.3` -> `v2.16.0` |

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### Release Notes

<details>
<summary>Tautulli/Tautulli (ghcr.io/tautulli/tautulli)</summary>

### [`v2.16.0`](https://github.com/Tautulli/Tautulli/blob/HEAD/CHANGELOG.md#v2160-2025-09-08)

[Compare Source](https://github.com/Tautulli/Tautulli/compare/v2.15.3...v2.16.0)

- Important Note!
  - Several security vulnerabilities have been identified in Tautulli versions <=2.15.3 (CVE-2025-58760, CVE-2025-58761, CVE-2025-58762, CVE-2025-58763). Users are strongly encouraged to update to the latest Tautulli version 2.16.x. (Thanks [@&#8203;d-xuan](https://github.com/d-xuan))
- UI:
  - Fix: Update poster click-through overlay to new Plex logo. ([#&#8203;2584](https://github.com/Tautulli/Tautulli/issues/2584)) (Thanks [@&#8203;TheMeanCanEHdian](https://github.com/TheMeanCanEHdian))
- Other:
  - Fix: Race condition in image cache directory creation ([#&#8203;2580](https://github.com/Tautulli/Tautulli/issues/2580)) (Thanks [@&#8203;keithah](https://github.com/keithah))
  - Fix: Validate image path in /image and /pms\_image\_proxy endpoints.
  - Fix: Validate image format in /pms\_image\_proxy endpoint.
  - Fix: Don't run git command with shell.

</details>

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Reviewed-on: https://gitea.alexlebens.dev/alexlebens/infrastructure/pulls/1403
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/applications/tautulli/values.yaml

@@ -11,7 +11,7 @@ tautulli:
         main:
           image:
             repository: ghcr.io/tautulli/tautulli
-            tag: v2.15.3
+            tag: v2.16.0
             pullPolicy: IfNotPresent
           env:
             - name: PUID