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/grafana-operator/Chart.lock

@@ -4,12 +4,12 @@ dependencies:
   version: 5.21.4
 - 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
 - name: redis-replication
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 1.0.4
-digest: sha256:5775ad67f466afd5e7bf986826e5385b4127c65bf81ed885df4690ffb8bd2876
-generated: "2026-02-07T02:28:49.454143056Z"
+digest: sha256:45fd579ed5393fb6aebc208b1ce79f803c34816e345d7ca0fed2907e710ec8c6
+generated: "2026-02-13T19:39:06.992748639Z"