Bump eslint and grunt-eslint

Bumps [eslint](https://github.com/eslint/eslint) to 9.39.2 and updates ancestor dependency [grunt-eslint](https://github.com/sindresorhus/grunt-eslint). These dependencies need to be updated together.


Updates `eslint` from 8.31.0 to 9.39.2
- [Release notes](https://github.com/eslint/eslint/releases)
- [Commits](eslint/eslint@v8.31.0...v9.39.2)

Updates `grunt-eslint` from 24.0.1 to 26.0.0
- [Release notes](https://github.com/sindresorhus/grunt-eslint/releases)
- [Commits](sindresorhus/grunt-eslint@v24.0.1...v26.0.0)

---
updated-dependencies:
- dependency-name: eslint
  dependency-version: 9.39.2
  dependency-type: indirect
- dependency-name: grunt-eslint
  dependency-version: 26.0.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]