emit formSubmitting when submitting change in multi url picker dialog (#10957)

src/Umbraco.Web.UI.Client/src/views/propertyeditors/multiurlpicker/multiurlpicker.controller.js

@@ -58,6 +58,8 @@ function multiUrlPickerController($scope, localizationService, entityResource, i
                 $scope.multiUrlPickerForm.maxCount.$setValidity("maxCount", true);
             }
             $scope.sortableOptions.disabled = $scope.renderModel.length === 1;
+            //Update value
+            $scope.model.value = $scope.renderModel;
         }
     );