微软Bot Framework文档中，关于Sign-in Card的一处代码错误及更正

Bot Framework文档出错处网址：https://docs.botframework.com/en-us/csharp/builder/sdkreference/attachments.html

出错代码：

 Activity replyToConversation = message.CreateReply(translateToPigLatin("Should go to conversation, sign-in card"));
 replyToConversation.Recipient = message.From;
 replyToConversation.Type = "message";
 replyToConversation.Attachments = new List<Attachment>();
 List<CardAction> cardButtons = new List<CardAction>();
 CardAction plButton = new CardAction()
 {
     Value = "https://<OAuthSignInURL>",
     Type = "signin",
     Title = "Connect"
 };
 cardButtons.Add(plButton);
 SigninCard plCard = new SigninCard(title: "You need to authorize me", button: plButton);
 Attachment plAttachment = plCard.ToAttachment();
 replyToConversation.Attachments.Add(plAttachment);
 var reply = await connector.Conversations.SendToConversationAsync(replyToConversation);

注意到第13行的SigninCard函数。回到Visual Studio按F12查看函数定义：

注意到两个可选参数是：text，buttons。

根据上下文，代码应改为：

SigninCard plCard = new SigninCard(text:"You need to authorize me", buttons:cardButtons);

或直接写成：

SigninCard plCard = new SigninCard("You need to authorize me", cardButtons);