freecad: don't compress QResources for python code

rcc automatically compresses resources above a certain size, but as
we found out the hard way, loading compressed resources from python
fails and may even coredump. As a workaround, force-disable compression
on resources in python code (c++ code seems to be fine compressed or not),
which re-enables several workbenches (most notably: Draft) at the cost
of a few megabytes of disk space.

Reported by: jeff@
MFH: 2020Q2