webhook.go
func (w *Webhook) SendLinkMsg(title, content, picURL, msgURL string) error {
	return w.SendPayload(&Payload{
		MsgType: "link",
		Link: struct {
			Text       string `json:"text"`
			Title      string `json:"title"`
			PicURL     string `json:"picUrl"`
			MessageURL string `json:"messageUrl"`
		}{
			Text:       content,
			Title:      title,
			PicURL:     picURL,
			MessageURL: msgURL,
		},
	})
}
func (w *Webhook) SendLinkMsg(title, content, picURL, msgURL string) error {
	return w.SendPayload(&Payload{
		MsgType: "link",
		Link: struct {
			Text       string `json:"text"`
			Title      string `json:"title"`
			PicURL     string `json:"picUrl"`
			MessageURL string `json:"messageUrl"`
		}{
			Text:       content,
			Title:      title,
			PicURL:     picURL,
			MessageURL: msgURL,
		},
	})
}
// SendLinkMsg 发送链接消息