https://api.weixin.qq.com/channels/ec/promoter/get_promote_product_list?access_token=ACCESS_TOKEN
请求参数
{
    "plan_type": 1,
    "next_key": "",
    "page_size": 20
}
返回
{
    "errcode": 0,
    "errmsg": "ok",
    "product_list": []
}