update script to build releases, to also build wheels

The commented-out command used "bdist", which produces a "dumb" format
(that's what the setuptools docs call it! it's an alias for
"bdist_dumb"). A tarball that can be extracted to / and installs a
system image containing e.g.  /usr/lib/python3.12 and /usr/share/, but
no metadata outside of that.

It apparently may have also generated a wheel at some point? But current
versions of setuptools do no such thing. And wheels are what we actually
want, since we uploaded them for years and they are faster for PyPI
users to install.

The canonical command name for producing wheels is actually
"bdist_wheel" instead of "bdist_dumb". No clue what setuptools changed,
about the latter, but the former definitely works.

packaging/builddist.sh

@@ -13,8 +13,7 @@ mkdir $GENDIR
 cp -r .git $GENDIR
 cd $GENDIR
 git reset --hard
-#python3 setup.py sdist bdist
-python3 setup.py sdist
+python3 setup.py sdist bdist_wheel
 cp dist/* ../dist
 cd ..
 rm -rf $GENDIR