Bump underscore.string from 3.3.4 to 3.3.5 (#303)

Bumps [underscore.string](https://github.com/epeli/underscore.string) from 3.3.4 to 3.3.5.
- [Release notes](https://github.com/epeli/underscore.string/releases)
- [Changelog](https://github.com/epeli/underscore.string/blob/master/CHANGELOG.markdown)
- [Commits](esamattis/underscore.string@3.3.4...3.3.5)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]