AbilityTask cause ability BP to be dirty upon global function remove event

Gameplay Ability BP is being set to dirty when function is removed from an unrelated actor Blueprint.

Reported by Licensee in 4.8.3 QA Build, Reproduced using Fortnite - CL - 2661312

1. Create a Blueprint derived from Gameplayability.
2. In the BP, create a custom event called Test
3. From Event ActivateAbility add a Wait Delay node
4. Save and Compile the BP
5. Create a new Blueprint derived from Actor
6. In the Actor BP, add a function
7. Save and Compile the Actor BP
8. Delete the added function

RESULTS: Actor and Gameability Blueprints are marked as dirty

EXPECTED: Actor Blueprint is marked dirty only