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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This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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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/harbor/Chart.lock

@@ -4,9 +4,9 @@ dependencies:
   version: 1.18.2
 - name: postgres-cluster
   repository: https://gitea.alexlebens.net/api/packages/alexlebens/helm
-  version: 7.7.0
+  version: 7.8.0
 - name: redis-replication
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 1.0.4
-digest: sha256:21ac96cde674b5db272eef5b4ae1aedea1e02c2b49dff88c2acb11282c3839e8
-generated: "2026-02-21T13:55:34.562766-06:00"
+digest: sha256:b28ba908b0b0ee05963163e98f6e2c5b828a61935077508670d8f91adf0f6d6e
+generated: "2026-02-27T18:16:26.310880738Z"

clusters/cl01tl/helm/harbor/Chart.yaml

@@ -21,7 +21,7 @@ dependencies:
     repository: https://helm.goharbor.io
   - name: postgres-cluster
     alias: postgres-18-cluster
-    version: 7.7.0
+    version: 7.8.0
     repository: https://gitea.alexlebens.net/api/packages/alexlebens/helm
   - name: redis-replication
     version: 1.0.4