adjusting path where the database file is saved, so the data persists after reboot

docker-compose.yml

@@ -4,6 +4,8 @@ services:
     image: postgres:18.3-alpine3.23
     env_file:
       - .env
+    environment:
+      - PGDATA=/var/lib/postgresql/data
     ports:
       - "5432:5432"
     volumes: