code: func (btn *Button) SetMiniprogramButton(name, url, appID, pagePath string) {
  	btn.Type = "miniprogram"
  	btn.Name = name
  	btn.URL = url
  	btn.AppID = appID
  	btn.PagePath = pagePath
  
  	btn.Key = ""
  	btn.MediaID = ""
  	btn.SubButtons = nil
  }
docs: //SetMiniprogramButton  设置 跳转小程序 类型按钮 (公众号后台必须已经关联小程序)