build(deps-dev): bump coveralls from 3.0.2 to 3.0.3
build(deps-dev): bump coveralls from 3.0.2 to 3.0.3

Bumps [coveralls](https://github.com/nickmerwin/node-coveralls) from 3.0.2 to 3.0.3.
- [Release notes](https://github.com/nickmerwin/node-coveralls/releases)
- [Commits](https://github.com/nickmerwin/node-coveralls/compare/3.0.2...3.0.3)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
jeffjewiss/broccoli-postcss-single