Remove QQ groups from official channels. (#10984)

README.md

@@ -59,8 +59,8 @@ Please follow the [REPORTING GUIDELINES](https://www.apache.org/foundation/polic
 # Contact Us
 * Mail list: **[email protected]**. Mail to `[email protected]`, follow the reply to subscribe the mail list.
 * Send `Request to join SkyWalking slack` mail to the mail list(`[email protected]`), we will invite you in.
+* For Chinese speaker, send `[CN] Request to join SkyWalking slack` mail to the mail list(`[email protected]`), we will invite you in.
 * Twitter, [ASFSkyWalking](https://twitter.com/AsfSkyWalking)
-* QQ Group: 901167865, 392443393
 * [bilibili B站 视频](https://space.bilibili.com/390683219)
 
 # Our Users