Bump pygithub from 1.46 to 1.47

Bumps [pygithub](https://github.com/PyGithub/PyGithub) from 1.46 to 1.47.
- [Release notes](https://github.com/PyGithub/PyGithub/releases)
- [Commits](PyGithub/PyGithub@v1.46...v1.47)

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

Author: dependabot-preview[bot]

dev-requirements.txt

@@ -20,7 +20,7 @@ mypy==0.770  # Type checking
 pip-check-reqs-pip-gte-20==2.0.3.1
 pydocstyle==5.0.2  # Lint docstrings
 pyenchant==3.0.1  # Bindings for a spellchecking sytem
-pygithub==1.46
+pygithub==1.47
 pylint==2.4.4  # Lint
 pyroma==2.6  # Packaging best practices checker
 pytest-cov==2.8.1  # Measure code coverage