Bump pytest from 5.3.2 to 5.3.5 (#20)

Bumps [pytest](https://github.com/pytest-dev/pytest) from 5.3.2 to 5.3.5.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@5.3.2...5.3.5)

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

requirements-dev.txt

@@ -39,7 +39,7 @@ pyflakes==2.1.1           # via flake8
 pygments==2.5.2           # via readme-renderer
 pylint==2.4.4
 pyparsing==2.4.5          # via packaging
-pytest==5.3.2
+pytest==5.3.5
 readme-renderer==24.0     # via twine
 regex==2019.12.9          # via black
 requests-toolbelt==0.9.1  # via twine