updated the menu section for the sticker sheet to Plugin UI kits

Author: dcaiced0

design/user-interface/sticker-sheet.md

@@ -1,5 +1,7 @@
 # Plugin sticker sheet
-This sticker sheet will cover the different UI surfaces available to plugins. It also includes examples of UI elements you can use to build your own plugin. Download the latest version from the Plugin Design Assets Github repository. 
+This sticker sheet will cover the different UI surfaces available to plugins. It also includes UI kits (MacOS and Windows) you can use to build your own plugin. 
+
+Download the latest version from the Plugin Design Assets Github repository. 
 
 #### [Download from GitHub](https://github.com/AdobeXD/plugin-design-assets/blob/master/Sticker_sheet_XD_plugins.xd?raw=true "Download from GitHub repo")