Use lib64 on 64-bit systems
Ideally, we would use the python3_sitearch macro directly, but we cannot do that for the nightlies, because that macro produces an absolute path, beginning with %{_prefix}/.
Thus we use lua to strip the unwanted prefix.
Ideally, we would use the python3_sitearch macro directly, but we cannot do that for the nightlies, because that macro produces an absolute path, beginning with %{_prefix}/.
Thus we use lua to strip the unwanted prefix.