widgets: remove hardcoded url attribute
widgets: remove hardcoded url attribute

No need for it

xrmx/django-fancytree,Ajeetlakhani/django-mptt-autocomplete,Ajeetlakhani/django-mptt-autocomplete,xrmx/django-fancytree,Ajeetlakhani/django-mptt-autocomplete,xrmx/django-fancytree