docs: fix requirements
docs: fix requirements

See https://github.com/sphinx-doc/sphinx/issues/3212

cezarsa/tsuru,tsuru/tsuru,guilhermebr/tsuru,tsuru/tsuru,ggarnier/tsuru,ArxdSilva/tsuru,ArxdSilva/tsuru,ggarnier/tsuru,ggarnier/tsuru,ggarnier/tsuru,ArxdSilva/tsuru,tsuru/tsuru,cezarsa/tsuru,guilhermebr/tsuru,tsuru/tsuru,cezarsa/tsuru,ArxdSilva/tsuru,guilhermebr/tsuru,cezarsa/tsuru,guilhermebr/tsuru