update discord & wechat link

README.md

@@ -30,7 +30,7 @@
 </p>
 
 <p align="center">
-    👋 join us on <a href="https://xxx" target="_blank">Discord</a> and <a href="https://xxx" target="_blank">WeChat</a>
+    👋 join us on <a href="https://discord.gg/AsQMhuMN" target="_blank">Discord</a> and <a href="https://cdn.vansin.top/internlm/mineru.jpg" target="_blank">WeChat</a>
 </p>
 </div>