chore(deps): update docker.io/library/postgres docker tag to v18

Author: renovate[bot]

services/c137/06-apps/compose.yaml

@@ -33,7 +33,7 @@ services:
     container_name: paperless-broker
     restart: unless-stopped
   paperless-db:
-    image: docker.io/library/postgres:17
+    image: docker.io/library/postgres:18
     container_name: paperless-db
     volumes:
       - "{{ appdata_path }}/apps/paperless/db:/var/lib/postgresql/data"