This commit makes the build of Python packages use `setuptools` instead
of the deprecated `distutils` in `setup.py` files. See
[PEP 632](https://peps.python.org/pep-0632/) for more information on the
deprecation of `distutils`.

Note that using `setuptools` instead of `distutils` removes the
following user warning messages when creating the `bdist` and `sdist` of
the consumer and producer projects:

```
/usr/lib/python3.8/distutils/dist.py:274: UserWarning: Unknown distribution option: 'setup_requires'
  warnings.warn(msg)
/usr/lib/python3.8/distutils/dist.py:274: UserWarning: Unknown distribution option: 'install_requires'
  warnings.warn(msg)
```

The numpy version is chosen based on the numpy version provided by
debian and centos for python < 3.7 and the version used by scipy wheels
for all other python version.

Additionally, the producer
and the consumer now have the same setup and install dependencies on
cython.