Get K-line

curl https://cloud-api.wooxpro.com/contract/public/kline?symbol=BTCUSDT&step=5&start_time=1662518172&end_time=1662518172

{
  "code": 1000,
  "trace": "0cc6f4c4-8b8c-4253-8e90-8d3195aa109c",
  "message": "Ok",
  "data": [{
    "timestamp": 1662518160,
    "open_price": "100",
    "close_price": "120",
    "high_price": "130",
    "low_price": "90",
    "volume": "941008"
    },
    {
      "timestamp": 1662518161,
      "open_price": "100",
      "close_price": "120",
      "high_price": "130",
      "low_price": "90",
      "volume": "941008"
    }
  ]
}