Bump pytest from 4.0.1 to 4.6.11

Bumps [pytest](https://github.com/pytest-dev/pytest) from 4.0.1 to 4.6.11.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/4.6.11/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@4.0.1...4.6.11)

---
updated-dependencies:
- dependency-name: pytest
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -1,3 +1,3 @@
 selenium==3.141.0
-pytest==4.0.1
+pytest==4.6.11
 Appium-Python-Client