Bump pytest from 5.1.3 to 5.2.0

Bumps [pytest](https://github.com/pytest-dev/pytest) from 5.1.3 to 5.2.0.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@5.1.3...5.2.0)

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

requirements.txt

@@ -4,7 +4,7 @@ kua==0.2
 werkzeug==0.16.0
 
 # dev
-pytest==5.1.3
+pytest==5.2.0
 pytest-runner==5.1
 pytest-asyncio==0.10.0
 coveralls==1.8.2