docs: don't repeat top-level dependencies #182

Job	Run time
Tests on other platforms (windows-2019, 3.10)	3m 27s
Tests on paywalled platforms (macos-13-xlarge, 3.12)	50s
Tox test (py38)	1m 59s
Tests on other platforms (windows-2022, 3.11)	3m 3s
Tox test (py39)	1m 58s
Tests on other platforms (windows-2022, 3.12)	3m 3s
Tox test (py310)	2m 2s
Tests on other platforms (macos-12, 3.11)	2m 39s
Tox test (py311)	1m 56s
Tests on other platforms (macos-13, 3.12)	2m 4s
Tox test (py312-cover)	3m 7s
Tox test (docs, graphviz)	2m 8s
Docker image	0s
PyPI packaging	0s
	28m 16s

Provide feedback