"Duplicate item named ... encountered while searching the Item Library" warning persists after renaming the variables in Graph Toolkit

Steps to reproduce:

1. Open the "GTK_ETs.zip" project
2. Open the "New Graph" asset in Graph Toolkit Editor
3. Create two variables with identical names ("Test")
4. Instantiate one variable as a node
5. Extend the connection and observe the Console (a warning is thrown about the duplicate variables)
6. Rename both variables to something different
7. Extend the connection and observe the Console

Actual results: "Duplicate item named "Variables/Test" encountered while searching the Item Library." warning is thrown

Expected results: No warnings are thrown 

Reproducible with versions: 0.1.0-exp.1 (6000.3.0a6), 6000.4.3f1, 6000.5.0b5, 6000.6.0a3

Tested on (OS): Windows 11 Pro (25H2)

Notes:

• Only resolvable if the variable is deleted and added again