remove depricated version tag and use .env for container mount path

docker-compose.yml

@@ -1,5 +1,3 @@
-version: '3.3'
-
 services:
   battlesnake:
     image: daniel156161/battlesnake
@@ -7,7 +5,7 @@ services:
     ports:
       - 8000:8000
     volumes:
-      - ./data:/app/data
+      - ${DOCKER_DATA_PATH}:/app/data
     build:
       context: ./
       dockerfile: Dockerfile

server/database/GameplayDatabase.py

@@ -1,7 +1,7 @@
 from quart_common.web.env import env_bool
 
-from datetime import datetime, timezone
 import asyncio, sqlite3, json, os, logging, sys
+from datetime import datetime, timezone
 from pathlib import Path
 
 logger = logging.getLogger(__name__)