[test] use assertIn where appropriate
Automatically generated with:
find -name unittest_*.py -o -name test_*.py | xargs sed -i -e 's/assertTrue(\([^,]*\) in \([^,]*\))/assertIn(\1, \2)/'
usr/bin/cubicweb-ctl usr/bin/
usr/lib/PY_VERSION/*-packages/cubicweb/cwctl.py
../cubicweb-ctl.bash_completion etc/bash_completion.d/cubicweb-ctl