[DOC]: Before/AfterSendGroupMsg doc are defined in 2 places, but the Interface Contract are Not same .

[hpsocket]

1. 群组相关回调（has groupID field）

• https://docs.openim.io/zh-Hans/restapi/webhooks/group/sendGroupMsgBefore
• https://docs.openim.io/zh-Hans/restapi/webhooks/group/sendGroupMsgAfter

3. 消息相关回调（has recvID field）

• https://docs.openim.io/zh-Hans/restapi/webhooks/msg/sendGroupMsgBefore
• https://docs.openim.io/zh-Hans/restapi/webhooks/msg/sendGroupMsgAfter