[test] Fix test breakage uncovered by previous changeset Now that Binary.__eq__ doesn't always return true, this test started failing. CWAttribute.defaultval is zpickled, and the description_format attribute is a String, meaning unicode, so adjust the expected test result.

usr/bin/cubicweb-ctl usr/bin/
usr/lib/PY_VERSION/*-packages/cubicweb/cwctl.py
../cubicweb-ctl.bash_completion etc/bash_completion.d/cubicweb-ctl