Bump black from 21.11b1 to 21.12b0

Bumps [black](https://github.com/psf/black) from 21.11b1 to 21.12b0.
- [Release notes](https://github.com/psf/black/releases)
- [Changelog](https://github.com/psf/black/blob/main/CHANGES.md)
- [Commits](https://github.com/psf/black/commits)

---
updated-dependencies:
- dependency-name: black
  dependency-type: direct:development
...

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

Author: dependabot[bot]

poetry.lock

@@ -21,7 +21,7 @@ mkdocs = "^1.2.3"
 mkdocs-material = "^8.0.3"
 
 [tool.poetry.dev-dependencies]
-black = "^21.11b1"
+black = "^21.12b0"
 codespell = "^2.1.0"
 flake8 = "^4.0.1"
 pep8-naming = "^0.12.1"