ENH: allow `black` in `notebooks` optional dependencies (#441) #848

Job	Run time
pytest / Determine job matrix	4s
style / Determine skipped pre-commit hooks	10s
doc / nb / Execute and build documentation	36s
doc / linkcheck / Check external links	20s
pytest / Run unit tests (3.10, ubuntu-24.04)	15s
pytest / Run unit tests (3.11, ubuntu-24.04)	13s
pytest / Run unit tests (3.9, ubuntu-24.04)	14s
pytest / Run unit tests (3.12, ubuntu-24.04, compwa_policy)	18s
pytest / Run unit tests (3.9, macos-14)	21s
style / Run local pre-commit hooks	44s
style / Run taplo through pre-commit	0s
doc / Upload to GitHub Pages	8s
style / Push changes	0s
	3m 23s

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