Hi Guix!

this patch (going to core-updates) removes files from the output of
python2 and python3, in an attempt to save some space. First, I noticed
that python3 shipped windows binaries in its source distribution and
installs them to the output, in lib/python3.8/distutils/command/*.exe,
lib/python3.8/site-packages/*.exe and
lib/python3.8/site-packages/pip/_vendor/distlib/*.exe. I remove them
from the snippet, so they should not be installed anymore.

I also noticed that python installs files that were built during the
test phase, so I remove them, but we need to check they are not
actually needed. Other distros ship them in a separate package, so
maybe we could have a separate test output if this is causing issues?

I haven't yet tested the patch, because it needs to rebuild part of the
bootstrap chain. I'll report progress and update my patch depending
on the results!