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/sonarr/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: volsync-target
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 0.7.0
-digest: sha256:809d9294747306a9ed571e380431437485648f23fabb7bfd8e42fd56fe142cba
-generated: "2026-02-21T20:05:33.736492151Z"
+digest: sha256:1eabced31f24346166b6054004278783b3c110f0eebfba1d3791e68ab7fd7c6f
+generated: "2026-02-27T18:21:03.635767093Z"

clusters/cl01tl/helm/sonarr/Chart.yaml

@@ -26,7 +26,7 @@ dependencies:
     version: 4.6.2
   - name: postgres-cluster
     alias: postgres-18-cluster
-    version: 7.7.0
+    version: 7.8.0
     repository: oci://harbor.alexlebens.net/helm-charts
   - name: volsync-target
     alias: volsync-target-config