[Feature] Support ESLint 9.x in @yarnpkg/eslint-config

[MikeMcC399]

• I'd be willing to implement this feature (contributing guide)
• This feature is important to have in this repository; a contrib plugin wouldn't do

Describe the user story

Use the npm module @yarnpkg/eslint-config@latest with a supported version of ESLint and a non-deprecated config.

Describe the solution you'd like

Due to configured dependencies, the highest ESLint version supported by @yarnpkg/eslint-config is the end-of-life version ESLint 8.x.

The lowest (and only currently) supported version of ESLint is ESLint 9.x, first released in Apr 2024. ESLint's supported configuration uses flat config files instead of deprecated config files.

PR #6276 already migrated to flat config.

According to the comment in that PR

I would have migrated us to Eslint 9, but eslint-plugin-react isn't compatible yet.

With minimum [email protected] ESLint v9 is supported, so that blocker has now been removed.

Multiple TypeScript formatting rules have moved to ESLint Stylistic and would need to be migrated.