fix(data persistency): docker volume persistency issue (#1139)

because of the missing /data path, there was an issue wherein the data
would be lost after docker compose down

overrides/compose.postgres.yaml

@@ -12,7 +12,7 @@ services:
     environment:
       POSTGRES_PASSWORD: ${DB_PASSWORD:?No db password set}
     volumes:
-      - db-data:/var/lib/postgresql
+      - db-data:/var/lib/postgresql/data
 
 volumes:
   db-data: