When re-categorizing variables within a blueprint collapsed categories pop open

If a user wants to change the category of a variable this will cause other categories that had previously been collapsed down for convenience to spring back open. This can make dragging and dropping more difficult when their are a lot of categories and/or variables.

1. Open the editor
2. Create a new blueprint
   Right click content browser > Blueprints > Actor
3. Open the new blueprint
4. Create several variables
5. Collapse the category that they are in
6. Change the Category of one of the new variables
   Select a variable > Details panel > Category > Type in a new category
7. Notice the previously collapsed category is no longer collapsed