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### _Why are the changes needed?_
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The Kyuubi documentation is missing about deploying Kyuubi on Kubernetes.
### _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/latest/develop_tools/testing.html#running-tests) locally before make a pull request
Closes#1457 from zwangsheng/doc/kyuubi_on_k8s.
Closes#1454
f916866f [zwangsheng] modify .html to .md
707368ce [zwangsheng] fix url & add todo
1a509781 [zwangsheng] Fix spelling
a624a602 [zwangsheng] fix
4ca74164 [zwangsheng] rename & add
Authored-by: zwangsheng <2213335496@qq.com>
Signed-off-by: ulysses-you <ulyssesyou@apache.org>