Bump pytest from 4.1.1 to 4.2.1

Bumps [pytest](https://github.com/pytest-dev/pytest) from 4.1.1 to 4.2.1.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@4.1.1...4.2.1)

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

Author: dependabot-support

poetry.lock

@@ -43,7 +43,7 @@ flake8-pyi = "^18.3"
 
 safety = "^1.8"
 
-pytest = "^4.1"
+pytest = "^4.2"
 pytest-cov = "^2.6"
 pytest-randomly = "^1.2"