build(deps-dev): bump commitizen from 2.6.0 to 2.8.0

Bumps [commitizen](https://github.com/commitizen-tools/commitizen) from 2.6.0 to 2.8.0.
- [Release notes](https://github.com/commitizen-tools/commitizen/releases)
- [Changelog](https://github.com/commitizen-tools/commitizen/blob/master/CHANGELOG.md)
- [Commits](commitizen-tools/commitizen@v2.6.0...v2.8.0)

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

Pipfile

@@ -11,7 +11,7 @@ pytest-cov = "==2.10.1"
 pytest-mock = "==3.3.1"
 mock = "==4.0.2"
 pre-commit = "==2.8.2"
-commitizen = "==2.6.0"
+commitizen = "==2.8.0"
 mypy = "==0.790"
 flake8 = "==3.8.4"
 controllerx = {path = ".", editable = true}