VectorDataWidget : Fix bool drawing for Qt5/PySide2
VectorDataWidget : Fix bool drawing for Qt5/PySide2

This fixes the one remaining (non-false-positive) issue found by the new qt5Check script.

hradec/gaffer,lucienfostier/gaffer,lucienfostier/gaffer,ImageEngine/gaffer,ivanimanishi/gaffer,andrewkaufman/gaffer,boberfly/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,appleseedhq/gaffer,johnhaddon/gaffer,hradec/gaffer,boberfly/gaffer,johnhaddon/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,hradec/gaffer,GafferHQ/gaffer,ivanimanishi/gaffer,lucienfostier/gaffer,andrewkaufman/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,appleseedhq/gaffer,boberfly/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,ivanimanishi/gaffer,hradec/gaffer,ImageEngine/gaffer,appleseedhq/gaffer,boberfly/gaffer,ivanimanishi/gaffer,appleseedhq/gaffer,johnhaddon/gaffer,hradec/gaffer,GafferHQ/gaffer,GafferHQ/gaffer,lucienfostier/gaffer,andrewkaufman/gaffer