chore: Update README.md

Author: maninhill

README.md

@@ -32,6 +32,7 @@ docker run -d --name=maxkb -p 8080:8080 -v ~/.maxkb:/var/lib/postgresql/data 1pa
 
 -   [使用手册](https://github.com/1Panel-dev/MaxKB/wiki/1-%E5%AE%89%E8%A3%85%E9%83%A8%E7%BD%B2)
 -   [论坛求助](https://bbs.fit2cloud.com/c/mk/11)
+-   [演示视频](https://www.bilibili.com/video/BV1BE421M7YM/)
 
 ## UI 展示