Bumps [prettier](https://github.com/prettier/prettier) from 2.1.2 to 2.2.0.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/master/CHANGELOG.md)
- [Commits](https://github.com/prettier/prettier/compare/2.1.2...2.2.0)
Signed-off-by: dependabot-preview[bot] <support@dependabot.com>