Update Documentation for `no-useless-fragment` Rule

[liby]

What kind of change does this PR introduce?

• [ ] Bugfix
• [ ] Feature
• [x] Docs
• [ ] New Binding issue #___
• [ ] Code style update
• [ ] Refactor
• [ ] Build-related changes
• [ ] Other, please describe:

Does this PR introduce a breaking change?

• [ ] Yes, and the changes were approved in issue #___
• [x] No

Checklist

• [ ] When resolving issues, they are referenced in the PR's title (e.g fix: remove a typo, closes #___, #___)
• [x] I have added a convincing reason for adding this feature, if necessary

Other information

This pull request updates the documentation to reflect the changes in the no-useless-fragment rule. The rule previously had an allowExpressions option, which controlled whether single expressions in a fragment were allowed. This option has been removed, and the rule now always allows single expressions in a fragment.

Motivation

• The removal of the allowExpressions option was not reflected in the documentation, potentially causing confusion for users transitioning from eslint-plugin-react to @eslint-react.
• By updating the documentation, we provide clear guidance on the current behavior of the no-useless-fragment rule.

[vercel[bot]]

@liby is attempting to deploy a commit to the Rel1cx's projects Team on Vercel.

A member of the Team first needs to authorize it.

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
eslint-react	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jun 25, 2024 8:00am

[liby]

Sorry, due to my negligence, I forgot to import Fragment in the example, which caused the code highlighting not to work. How do we generally tend to solve this issue?

1. I submit an additional fix PR
2. Revert this PR (or force push overwrite on the main branch), and I will resubmit this PR after fixing it
3. Other

In addition, I found that after merging, you used my PR title as the commit message instead of following the conventional commit message format.