Duplicating an overridden function graph causes input/output pins to double

This is caused by the same thing that causes this: https://jira.it.epicgames.net/browse/UE-58390

FBlueprintEditorUtils::PromoteGraphFromInterfaceOverride is the cause of this behavior 

1. Create an actor bp
2. Add a function with an input and output
3. Create a child BP that inherits from that
4. Override the function 
5. Select the function in the details panel
6. Duplicate (CTRL + W)

Results: All input and output pins are doubled