build(deps-dev): bump grunt-contrib-jshint from 1.1.0 to 2.1.0

Bumps [grunt-contrib-jshint](https://github.com/gruntjs/grunt-contrib-jshint) from 1.1.0 to 2.1.0.
- [Release notes](https://github.com/gruntjs/grunt-contrib-jshint/releases)
- [Changelog](https://github.com/gruntjs/grunt-contrib-jshint/blob/master/CHANGELOG)
- [Commits](gruntjs/grunt-contrib-jshint@v1.1.0...v2.1.0)

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