[TASK][EASY] Kyuubi documentation improvements

### Code of Conduct

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

### Search before creating

- [X] I have searched in the [task list](https://github.com/orgs/apache/projects/296) and found no similar tasks.

### Mentor

- [ ] I have sufficient knowledge and experience of this task, and I volunteer to be the mentor of this task to guide contributors to complete the task.

### Skill requirements

- Basic knowledge of Apache Kyuubi
- Good English tech article writing skills

### Background and Goals

This is kind of an umbrella task, anyone who can improve the Kyuubi docs by sending PRs directly, for example

- fix typos or grammar issues
- polish the expressions or statements
- write articles to introduce how to integrate Kyuubi with other popular projects or services
- write articles to introduce the user case
- ...

### Implementation steps

The maintainers/committers would classify your PR into different levels based on the content of certain PRs, e.g.

"fix typos or grammar issues" is generally a TRIVIAL task.

"write articles to introduce how to integrate Kyuubi with some AWS services" could be an EASY or MEDIUM task

### Additional context

Introduction of https://github.com/apache/kyuubi/issues/6232

No specific file, test, or entry point is named. Start by reviewing the Kyuubi documentation and related issue #6232, then choose a bounded change such as a typo fix or an AWS integration or use-case article. Done means the selected documentation improvement is complete and submitted as a focused PR.

Written by the indexing model from the issue text.