### _Why are the changes needed?_
https://github.com/apache/incubator-kyuubi/issues/1174
Now kyuubi servcie uses kerberos authentication and registers with the zookeeper to the node information, but the client cannot connect to the service.
### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible
- [x] 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#1175 from cxzl25/KYUUBI-1174.
Closes#1174
386c7d57 [sychen] add comment
dc37a158 [sychen] respect user's setting
97401a96 [sychen] update settings.md
fd8cceda [sychen] Service discovery supports kerberos
Authored-by: sychen <sychen@trip.com>
Signed-off-by: Kent Yao <yao@apache.org>
6420a7eb04