Binance Connector: use symbol as trading_pair in _all_trade_updates_for_order method

[astra-a]

Describe the bug

In _all_trade_updates_for_order of binance_exchange.py, the symbol is assigned in trading_pair field of TradeUpdate class. Btw, the symbol(BTCUSDT) and trading_pair(BTC-USDT) are different in binance.

Steps to reproduce

1. It works well right now
2. Some errors will occur if using the trading_pair field in TradeUpdate class to implement some logics in the future.

Release version

v1.25.0

Type of installation

Source

Attach required files

No response