docs(README): add youtube channel badge (#808)

README-CN.md

@@ -4,6 +4,7 @@
 [![Slack Invite](<https://kuiper-slack-invite.emqx.io/badge.svg>)](https://kuiper-slack-invite.emqx.io/)
 [![Twitter](https://img.shields.io/badge/Follow-EMQ-1DA1F2?logo=twitter)](https://twitter.com/EMQTech)
 [![问答社区](https://img.shields.io/badge/问答社区-Kuiper-yellow)](https://askemq.com/c/kuiper/)
+[![YouTube](https://img.shields.io/badge/Subscribe-EMQ%20中文-FF0000?logo=youtube)](https://www.youtube.com/channel/UCir_r04HIsLjf2qqyZ4A8Cg)
 
 [English](README.md) | [简体中文](README-CN.md)
 

README.md

@@ -5,6 +5,7 @@
 [![Slack Invite](<https://kuiper-slack-invite.emqx.io/badge.svg>)](https://kuiper-slack-invite.emqx.io/)
 [![Twitter](https://img.shields.io/badge/Follow-EMQ-1DA1F2?logo=twitter)](https://twitter.com/EMQTech)
 [![Community](https://img.shields.io/badge/Community-Kuiper-yellow?logo=github)](https://github.com/emqx/kuiper/discussions)
+[![YouTube](https://img.shields.io/badge/Subscribe-EMQ-FF0000?logo=youtube)](https://www.youtube.com/channel/UC5FjR77ErAxvZENEWzQaO5Q)
 
 [English](README.md) | [简体中文](README-CN.md)