fixed docker compose refer

Author: s3inlc

.devcontainer/docker-compose.postgres.yml

@@ -31,7 +31,7 @@ services:
     image: postgres:13
     restart: always
     volumes:
-      - db:/var/lib/postgresql/data
+      - hashtopolis-db-dev:/var/lib/postgresql/data
     environment:
       POSTGRES_DB: hashtopolis
       POSTGRES_USER: hashtopolis