remove some links that contians indecent content (#5560)

Author: yangzhg

docs/en/community/gitter.md

@@ -48,10 +48,6 @@ You can use Gitter as well as Wechat, and get functions that are more comfortabl
 
 Don't forget to click on the Pentagon in the upper right corner to collect, which will make the chat room easier for you to find.
 
-For more gitter usage tips, you can refer to:
-
-[http://www.gitter.net.cn/book/gitter/roomsettings-1.html](http://www.gitter.net.cn/book/gitter/roomsettings-1.html)
-
 ## Install Mobile Client
 
 You can download Gitter's mobile client and participate in technical discussions on your mobile phone at any time and anywhere. Download links:

docs/zh-CN/community/gitter.md

@@ -48,10 +48,6 @@ Doris 和很多其他的开源项目一样，可以使用 Gitter 作为技术交
 
 已经加入聊天室的伙伴别忘记点击右上角的五角星进行收藏，这样会让本聊天室更容易被您自己找到。
 
-更多 gitter 使用技巧，可以参考：
-   
-[http://www.gitter.net.cn/book/gitter/roomsettings-1.html](http://www.gitter.net.cn/book/gitter/roomsettings-1.html)
-
 ## 安装手机客户端
 
 您可以下载 Gitter 的手机客户端，在手机上也随时随地的参与到技术讨论中，下载链接：