### _Why are the changes needed?_
close https://github.com/apache/kyuubi/issues/4881
### _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#4886 from rhh777/jdbcengine.
Closes#4881
e0439f8e6 [haorenhui] [KYUUBI #4881] update settings.md
d667d8fe8 [haorenhui] [KYUUBI #4881] update conf/docs
cba06b4b9 [haorenhui] [KYUUBI #4881] simplify code
80be4d27c [haorenhui] [KYUUBI #4881] fix style
4f0fa3ab2 [haorenhui] [KYUUBI #4881] JDBCEngine performs initialization sql
Authored-by: haorenhui <haorenhui@kingsoft.com>
Signed-off-by: Cheng Pan <chengpan@apache.org>