update README.md.

Signed-off-by: blue <825657193@qq.com>

README.md

@@ -232,7 +232,7 @@ wsApi.onmessage((cmd,msgInfo) => {
 #### 嘿嘿
 ![输入图片说明](%E6%88%AA%E5%9B%BE/%E5%BE%AE%E4%BF%A1%E6%94%B6%E6%AC%BE%E7%A0%81.png)
 
-悄悄放个码在这，宝子们..你懂我意思吧
+悄悄放个二维码在这，宝子们..你懂我意思吧