install document update needed

[yubin-ai]

I am trying to install cellxgene for M2 chip MacBook and the command in the doc:

conda create --yes -n cellxgene python=3.7

does not work in Mac anymore. it seems python 3.7 is outdated for the M chip Mac.

└─ python 3.7**  does not exist (perhaps a typo or a missing channel).

and all the packages associated with cellxgene are pretty old and do not work with latest scanpy et al anymore. it would be nice to have an updated version of env/package requirement.