Bump setuptools from 50.3.2 to 51.0.0

Bumps [setuptools](https://github.com/pypa/setuptools) from 50.3.2 to 51.0.0.
- [Release notes](https://github.com/pypa/setuptools/releases)
- [Changelog](https://github.com/pypa/setuptools/blob/master/CHANGES.rst)
- [Commits](pypa/setuptools@v50.3.2...v51.0.0)

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

requirements/testing.txt

@@ -10,6 +10,6 @@ pylint-strict-informational==0.1
 pytest==6.1.2
 pytest-cov==2.10.1
 pytest-timeout==1.4.2
-setuptools==50.3.2
+setuptools==51.0.0
 tox==3.20.1
 mypy==0.790