### _Why are the changes needed?_
Bump up markdown version from 3.3.7 to 3.4.1, the sphinx-markdown-tables has been upgraded to 0.0.17 in which the regression is resolved. It now conflicts with markdown 3.3.7
### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible
- [ ] Add screenshots for manual tests if appropriate
- [x] [Run test](https://kyuubi.readthedocs.io/en/master/develop_tools/testing.html#running-tests) locally before make a pull request
Closes#4340 from yaooqinn/markdown.
Closes#4340
da950a74 [Kent Yao] Bump up markdown version form 3.3.7 to 3.4.1
Authored-by: Kent Yao <yao@apache.org>
Signed-off-by: Cheng Pan <chengpan@apache.org>