[Subtask] Access Kyuubi using MySQL client documentation

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

### Search before asking

- [X] I have searched in the [issues](https://github.com/apache/incubator-kyuubi/issues) and found no similar issues.

### Describe the subtask

Kyuubi supports MySQL protocol since https://github.com/apache/incubator-kyuubi/issues/1219, it allows user uses `mysql` command and MySQL JDBC connector to connect Kyuubi.

### Parent issue

https://github.com/apache/incubator-kyuubi/issues/3039

### Are you willing to submit PR?

- [ ] Yes. I can submit a PR independently to improve.
- [ ] Yes. I would be willing to submit a PR with guidance from the Kyuubi community to improve.
- [ ] No. I cannot submit a PR at this time.

Start by reading parent issue #3039 and the referenced issue #1219 to understand the intended documentation scope. Check the existing Kyuubi documentation for MySQL client and JDBC connection guidance; done means users can find accurate instructions for connecting with the mysql command and MySQL JDBC connector.

Written by the indexing model from the issue text.