fixed d'n'd when test item dragged outside the tree - returned 'target' is None in those cases which caused AttributeError stacktrace
fixed d'n'd when test item dragged outside the tree - returned 'target' is None in those cases which caused AttributeError stacktrace

HelioGuilherme66/RIDE,fingeronthebutton/RIDE,caio2k/RIDE,robotframework/RIDE,robotframework/RIDE,HelioGuilherme66/RIDE,HelioGuilherme66/RIDE,caio2k/RIDE,robotframework/RIDE,fingeronthebutton/RIDE,HelioGuilherme66/RIDE,caio2k/RIDE,fingeronthebutton/RIDE,robotframework/RIDE