Update grunt-contrib-coffee requirement from ^0.13.0 to ^2.1.0
Update grunt-contrib-coffee requirement from ^0.13.0 to ^2.1.0

Updates the requirements on [grunt-contrib-coffee](https://github.com/gruntjs/grunt-contrib-coffee) to permit the latest version.
- [Release notes](https://github.com/gruntjs/grunt-contrib-coffee/releases)
- [Changelog](https://github.com/gruntjs/grunt-contrib-coffee/blob/master/CHANGELOG)
- [Commits](https://github.com/gruntjs/grunt-contrib-coffee/compare/v0.13.0...v2.1.0)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
leny/grunt-todo,leny/grunt-todo