Can not place multiple orders with JSON object param.

[vuongnq10]

Issue subject

Source code comes from here
https://github.com/binance/binance-futures-connector-node/blob/main/examples/um_futures/account/placeMultipleOrders.js

const batchOrders = [
  { symbol: 'BNBUSDT', ...others},
  { symbol: 'BNBUSDT', ...others }
]
umFuturesClient
  .placeMultipleOrders(batchOrders)
  .then((response) => console.log(response))
  .catch(console.error)

Expected behaviour

I believe that the request params should be transformed to string before sending

const batchOrders = [
  { symbol: 'BNBUSDT', ...others},
  { symbol: 'BNBUSDT', ...others }
]
umFuturesClient
  .placeMultipleOrders(JSON.stringify(batchOrders))
  .then((response) => console.log(response))
  .catch(console.error)

I'm running my trading bot with this config and it works well

Actual behaviour

N/A

Steps to reproduce

N/A

Environment

N/A