setup: stop packaging python3.dll and python3X.dll in the wheel distribution
Now that exewrapper is smart enough to find the DLLs it needs without help from
the build script, backout ed286d150aa8 and 2960b7fac966. Note that this will
require deleting the build/lib.win-amd64-3.X directory to actually remove it
from the final wheel.
Differential Revision: https://phab.mercurial-scm.org/D11455