这个文档https://developers.weixin.qq.com/doc/offiaccount/Message_Management/One-time_subscription_info.html
公众号一次性订阅消息列表下，“接入说明”链接无法访问https://open.weixin.qq.com/cgi-bin/showdocument?action=dir_list&t=resource/res_list&verify=1&id=open1500434436_aWfqW&token=&lang=zh_CN
