Remove unused var

Author: MDUYN

investing_algorithm_framework/services/trade_service/trade_service.py

@@ -295,7 +295,6 @@ def _create_trade_metadata_with_sell_order_and_trades(
         """
         sell_order_id = sell_order.id
         updated_at = sell_order.updated_at
-        sell_amount = sell_order.amount
         sell_price = sell_order.price
 
         for trade_data in trades: