Bump pytest from 4.4.1 to 6.2.2 in /tests

Bumps [pytest](https://github.com/pytest-dev/pytest) from 4.4.1 to 6.2.2.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@4.4.1...6.2.2)

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

Author: dependabot[bot]

tests/requirements.txt

@@ -1,3 +1,3 @@
 requests==2.25.1
 boto3==1.17.5
-pytest==4.4.1
+pytest==6.2.2