Update SUMMARY.md

Author: madsrasmussen

17/umbraco-cms/SUMMARY.md

@@ -247,6 +247,10 @@
   * [Integrate Property Editors](customizing/property-editors/integrate-property-editors.md)
   * [Tracking References](customizing/property-editors/tracking.md)
   * [Property Dataset](customizing/property-editors/property-dataset.md)
+* [Utilities](customizing/utilities/README.md)
+  * [Modals](customizing/utilities/modals.md)
+    * [Confirm Dialog](customizing/utilities/modals/confirm-dialog.md)
+  * [UI Sorting](customizing/utilities/sorting.md)
 * [Workspaces](customizing/workspaces.md)
 * [Umbraco Package](customizing/umbraco-package.md)
 * [UI Library](customizing/ui-library.md)