[Sketcher] Ensure All Reference Constraints are Read Only in the Property Editor

src/Mod/Sketcher/Gui/PropertyConstraintListItem.cpp

@@ -109,6 +109,7 @@ void PropertyConstraintListItem::initialize()
 
             item->bind(list->createPath(id - 1));
             item->setAutoApply(false);
+            item->setReadOnly(!(*it)->isDriving);
         }
     }