请求信息：
{
    "combine_appid":"wxe0a*********",
    "sub_orders":[
        {
            "mchid":"15********",
            "out_trade_no":"202003291955yj",
            "description":"测试关闭",
            "sub_mchid":"158********"
        }
    ],
    "combine_out_trade_no":"202003291955"
}

请求地址:https://api.mch.weixin.qq.com/v3/combine-transactions/out-trade-no/202003291955/close

API文档地址：https://pay.weixin.qq.com/wiki/doc/apiv3/wxpay/pay/combine/chapter3_4.shtml

返回信息：400BadRequest