* Update `@typescript-eslint` packages * Install `typescript` * Tweaks snapshot tests * Tweaks error files * Add tests for `using` with types * Add changelog * Update misc tests * Update snapshots * Revert misc tests and remove `typescript` * Update changelog_unreleased/typescript/15321.md Co-authored-by: fisker Cheung <lionkay@gmail.com> * Fix file name typo * Keep valid file * Update tests * Update changelog_unreleased/typescript/15321.md Co-authored-by: fisker Cheung <lionkay@gmail.com> * Remove non-existing filenames. --------- Co-authored-by: fisker Cheung <lionkay@gmail.com>