### _Why are the changes needed?_
Supply a FTS connector doc in Hive
### _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#4337 from a49a/hive-fts-doc.
Closes#3085
7ec5b73f [Luning Wang] [KYUUBI #3085][DOCS] Add Hive FTS Connector
Authored-by: Luning Wang <wang4luning@gmail.com>
Signed-off-by: Cheng Pan <chengpan@apache.org>