Bump pytest from 5.4.3 to 6.0.2

Bumps [pytest](https://github.com/pytest-dev/pytest) from 5.4.3 to 6.0.2.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@5.4.3...6.0.2)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

poetry.lock

@@ -10,7 +10,7 @@ pre-commit = "^2.7.1"
 black = "^20.8b1"
 
 [tool.poetry.dev-dependencies]
-pytest = "^5.2"
+pytest = "^6.0"
 
 [build-system]
 requires = ["poetry>=0.12"]