chore(deps): update postgres-cluster docker tag to v7.6.0 (#3958)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [postgres-cluster](https://github.com/cloudnative-pg/cloudnative-pg) | minor | `7.5.1` → `7.6.0` |

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Reviewed-on: #3958
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/helm/postiz/Chart.lock

@@ -7,7 +7,7 @@ dependencies:
   version: 2.3.0
 - name: postgres-cluster
   repository: oci://harbor.alexlebens.net/helm-charts
-  version: 7.5.1
+  version: 7.6.0
 - name: redis-replication
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 1.0.4
@@ -17,5 +17,5 @@ dependencies:
 - name: volsync-target
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 0.7.0
-digest: sha256:399468e311fa4b9a52681770fcf5f0c247764b99883c847a18c166a1d40726be
-generated: "2026-02-07T02:32:49.436802609Z"
+digest: sha256:7a66fea0f9a00845356101b24bef2ca4e43f7089179d73b62e6330b30d37666f
+generated: "2026-02-13T19:42:39.515074076Z"