Bump @eslint/js from 9.20.0 to 9.21.0

Bumps [@eslint/js](https://github.com/eslint/eslint/tree/HEAD/packages/js) from 9.20.0 to 9.21.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/main/CHANGELOG.md)
- [Commits](https://github.com/eslint/eslint/commits/v9.21.0/packages/js)

---
updated-dependencies:
- dependency-name: "@eslint/js"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -83,7 +83,7 @@
     "micromark-util-types": "2.0.1"
   },
   "devDependencies": {
-    "@eslint/js": "9.20.0",
+    "@eslint/js": "9.21.0",
     "@stylistic/eslint-plugin": "4.0.1",
     "ajv": "8.17.1",
     "ava": "6.2.0",