Add database and redis environment variables

.env.example

@@ -7,3 +7,5 @@ DEMO_QUOTE_ASSET=USDT
 COINEX_API_BASE=https://api.coinex.com/v2
 COINEX_WS_SPOT=wss://socket.coinex.com/v2/spot
 DEFAULT_MARKET=BTCUSDT
+DATABASE_URL=postgresql+psycopg://trade:trade@postgres:5432/trade
+REDIS_URL=redis://redis:6379/0