Hitbtc3 fetchOrderTrades
Hitbtc3 fetchOrderTrades

Added margin functionality to fetchOrderTrades:
```
hitbtc3.fetchOrderTrades (841283764693)
2022-03-24T02:18:04.714Z iteration 0 passed in 243 ms

        id | order |     timestamp |                 datetime |   symbol | type | side | takerOrMaker |    price |  amount
|      cost |                                     fee |                                      fees
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1655137410 |       | 1648086557205 | 2022-03-24T01:49:17.205Z | BTC/USDT |      |  buy |        taker | 42754.43 | 0.00002
| 0.8550886 | {"cost":0.0021377215,"currency":"USDT"} | [{"currency":"USDT","cost":0.0021377215}]
1 objects
```

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