Bump eslint from 9.19.0 to 9.21.0

Bumps [eslint](https://github.com/eslint/eslint) from 9.19.0 to 9.21.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/main/CHANGELOG.md)
- [Commits](eslint/eslint@v9.19.0...v9.21.0)

---
updated-dependencies:
- dependency-name: eslint
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -35,7 +35,7 @@
     "@web/dev-server-esbuild": "^1.0.3",
     "@web/rollup-plugin-html": "^2.3.0",
     "@web/test-runner": "^0.19.0",
-    "eslint": "^9.19.0",
+    "eslint": "^9.21.0",
     "open-props": "^1.7.12",
     "postcss": "^8.5.1",
     "postcss-cli": "^11.0.0",