Fix PYTHONARCH usage

Signed-off-by: Mark Hymers <mark.hymers@hankel.co.uk>
1 job for master in 1 minute and 24 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build Test
failed #1623
build_test

00:01:24

 
Name Stage Failure
failed
build_test Build Test
$ make testv
python3 setup.py build
running build
running build_py
cd build && PYTHONPATH=lib/:${PYTHONPATH} nosetests3 --with-coverage --cover-package=anamnesis -c ../nose.cfg -s -v lib/anamnesis
/bin/sh: 1: nosetests3: not found
Makefile:34: recipe for target 'testv' failed
make: *** [testv] Error 127
ERROR: Job failed: exit code 1