chore(deps): update postgres-cluster docker tag to v7.8.0 (#4278)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [postgres-cluster](https://github.com/cloudnative-pg/cloudnative-pg) | minor | `7.7.0` → `7.8.0` |

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### Configuration

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Reviewed-on: #4278
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: 7.7.0
+  version: 7.8.0
 - name: redis-replication
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 1.0.4
-digest: sha256:5ac6b293226ce26c698158b2b44dcbe3907ca37aa4046d392653577ca274f0e3
-generated: "2026-02-21T13:56:51.393846-06:00"
+digest: sha256:a8bba8dab827a4e382145970bc50b12f6354576826b8f413fa8f4497c9569113
+generated: "2026-02-27T18:18:14.173283762Z"

clusters/cl01tl/helm/outline/Chart.yaml

@@ -27,7 +27,7 @@ dependencies:
     version: 2.3.0
   - name: postgres-cluster
     alias: postgres-18-cluster
-    version: 7.7.0
+    version: 7.8.0
     repository: oci://harbor.alexlebens.net/helm-charts
   - name: redis-replication
     version: 1.0.4