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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Reviewed-on: #4278
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/helm/directus/Chart.lock

@@ -4,9 +4,9 @@ dependencies:
   version: 4.6.2
 - 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:c769752a4e07a8313c0fa354e80fcaeb0175c599f49c03afe55b75d4e8823d9e
-generated: "2026-02-21T13:55:04.630414-06:00"
+digest: sha256:8385abb48136f3a01c3024e2fffd1e4cc87468ce6d27d2e6d2dae5a8f4bfa9c8
+generated: "2026-02-27T18:15:08.245144791Z"