fix(dropdown): only preventdefault on hide for associating labels

The implemented preventDefault avoided a dropdown by reopening when clicking on the associated label instead of the dropdown itself.
Unfortunately this also stops other events in some situations which do not belong to the dropdown itself.
This PR now only prevents the event when the special case of the associated label was the target.

Closes #861

src/definitions/modules/dropdown.js

@@ -1201,7 +1201,9 @@ $.fn.dropdown = function(parameters) {
             },
             hide: function(event) {
               if(module.determine.eventInModule(event, module.hide)){
+                if(element.id && $(event.target).attr('for') === element.id){
                   event.preventDefault();
+                }
               }
             }
           },