Better documentation to pull from pephub into Python

[donaldcampbelljr]

• [x] add some better documentation for using pephubclient api within python

        > there was no clear way to pull from pephub into Python (I guess pephubclient can do this? Possibly just need docs)

For using looper with pephub looks like there is documentation: https://looper.databio.org/en/dev/hello-world-pephub/

However, it does appear that our pephubclient api docs could be expanded. There is currently only a light readme.

Originally posted by @donaldcampbelljr in https://github.com/pepkit/looper/issues/414#issuecomment-1775484307

[khoroshevskyi]

This issue was solved, and docs were added: https://pep.databio.org/pephub/developer/pephubclient/phc_usage/