setup.py: rm unused WINDOWS_DESCRIPTION
setup.py: rm unused WINDOWS_DESCRIPTION

alexandrul-ci/robotframework,HelioGuilherme66/robotframework,robotframework/robotframework,alexandrul-ci/robotframework,robotframework/robotframework,alexandrul-ci/robotframework,HelioGuilherme66/robotframework,HelioGuilherme66/robotframework,robotframework/robotframework,alexandrul-ci/robotframework,alexandrul-ci/robotframework