docs building using readthedocs.yml version 2

[weikang9009]

migrate from readthedocs configuration file v1 to v2

docs building is successful on my fork

[slumnitz]

Hi @weikang9009, thank you for changing this and the work you are putting into!
Looks great to me too!

On that note, I noticed plot_local_autocorrelation(), spatial_weights() and some via_choropleth() functionality visualisations do not build. Likely due to another issue.

[weikang9009]

@slumnitz I took another look at the readthedocs building process. It seems that geopandas is not properly installed using pip. At first, it complains about descartes (ModuleNotFoundError: No module named 'descartes'). After I explicitly included descartes in requirements_dev.txt, it complains about Missing package rtree``.

Not sure about the best way to proceed since conda install geopandas will use a lot of resources and readthedocs might not allow it .