### _Why are the changes needed?_
Add the Hudi connector doc for Spark SQL Query Engine
### _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
- [ ] [Run test](https://kyuubi.apache.org/docs/latest/develop_tools/testing.html#running-tests) locally before make a pull request
Closes#3099 from deadwind4/hudi-spark-doc.
Closes#3068
fcd2cf6a [Luning Wang] update doc
0ee870d9 [Luning Wang] [KYUUBI #3068][DOC] Add the Hudi connector doc for Spark SQL Query Engine
Authored-by: Luning Wang <wang4luning@gmail.com>
Signed-off-by: Kent Yao <yao@apache.org>