Update setuptools requirement from ~=51.1.0 to ~=51.1.1

Updates the requirements on [setuptools](https://github.com/pypa/setuptools) to permit the latest version.
- [Release notes](https://github.com/pypa/setuptools/releases)
- [Changelog](https://github.com/pypa/setuptools/blob/main/CHANGES.rst)
- [Commits](pypa/setuptools@v51.1.0...v51.1.1)

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

requirements.txt

@@ -1,4 +1,4 @@
-setuptools~=51.1.0
+setuptools~=51.1.1
 lxml~=4.6.2
 pytz~=2020.5
 pytest-cov~=2.10.1