Drop `setuptools` install requirement
Drop `setuptools` install requirement

We only use `setuptools` for the build. It is not used at install time.
So go ahead and drop it from the install requirements.

DudLab/nanshe,DudLab/nanshe,nanshe-org/nanshe,nanshe-org/nanshe,jakirkham/nanshe,jakirkham/nanshe