chore(deps): update container image mariadb to v13.7.8@604f0b6 by renovate (#20129)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [mariadb](https://truecharts.org/charts/stable/mariadb)
([source](https://togithub.com/prometheus/mysqld_exporter)) | patch |
`13.7.7` -> `13.7.8` |

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> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.

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charts/stable/bookstack/Chart.yaml

@@ -17,7 +17,7 @@ dependencies:
     tags: []
     import-values: []
   - name: mariadb
-    version: 13.7.7
+    version: 13.7.8
     repository: oci://tccr.io/truecharts
     condition: mariadb.enabled
     alias: ""
@@ -45,4 +45,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/bookstack
   - https://ghcr.io/linuxserver/bookstack
 type: application
-version: 13.8.12
+version: 13.8.13