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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<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My4zLjYiLCJ1cGRhdGVkSW5WZXIiOiI0My4zLjYiLCJ0YXJnZXRCcmFuY2giOiJtYWluIiwibGFiZWxzIjpbImNoYXJ0IiwiaW1hZ2UiXX0=-->

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

clusters/cl01tl/helm/freshrss/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: volsync-target
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 0.7.0
-digest: sha256:d3129463df789e53981fc7e57b5574d6eba00a44f4b9f906efacf563d70b36f3
-generated: "2026-02-07T02:28:08.830228688Z"
+digest: sha256:ced68d71c144b81655460354d6183aec9fd193e5adf1d361af7ad96383c37d07
+generated: "2026-02-13T19:38:06.20283888Z"

clusters/cl01tl/helm/freshrss/Chart.yaml

@@ -26,7 +26,7 @@ dependencies:
     version: 2.3.0
   - name: postgres-cluster
     alias: postgres-18-cluster
-    version: 7.5.1
+    version: 7.6.0
     repository: oci://harbor.alexlebens.net/helm-charts
   - name: volsync-target
     alias: volsync-target-data