Undo rename of Anim Curve in Anim Curves tab duplicates that curve

Undoing the renaming of an Anim Curve in the Anim Curve tab causes the curve to be duplicated.

Not a regression from 4.16.2.

1. Open QAGame
2. Open TestMorph asset
3. Open Window -> Anim Curves tab
4. Rename Jaw_Drop to CurveTest in the Anim Curves tab
5. Undo rename

Result: Two curves are shown with the name Jaw_Drop

Expected: Rename is undone and only one curve exists with Jaw_Drop name