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/outline/Chart.lock

@@ -7,9 +7,9 @@ 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
-digest: sha256:5beab8bbe25bbcafae4cb9a55494212b00f8f52053ec0ee545288a23bc6ea61c
-generated: "2026-02-07T02:32:25.090868738Z"
+digest: sha256:be667d9eef8a0d703796e380129226fd20d3192289249152a7bc78f61d46cf4d
+generated: "2026-02-13T19:41:57.448009772Z"