订阅消息和服务通知的区别
你好，接口权限不一致：https://developers.weixin.qq.com/doc/offiaccount/Getting_Started/Explanation_of_interface_privileges.html
群发次数区别：https://developers.weixin.qq.com/community/develop/doc/000e06e2e983c0de357acaa0151809?highLine=%25E7%25BE%25A4%25E5%258F%2591%25E6%25AC%25A1%25E6%2595%25B0
