How to reproduce:
1. Create and open a new UPR project
2. Open the "InputSystem_Actions" asset in the Input Actions Editor window
3. Make any change to the file
4. Attempt to close the Editor
5. In the "Input Action Asset has been modified" dialog box, press Cancel
6. Observe the Editor

Actual result: The Editor closes
Expected result: The Editor stays open

Reproducible in: 1.8.0-pre.2 (2023.3.0a2), 1.18.0 (6000.5.0a7)
Not reproducible in: 1.8.0-pre.1 (2023.3.0a2)

Reproduced on: Windows 11 Pro (25H2)
Not reproduced on: No other environment tested

Note: Before the regression, the Input Actions Editor window would be duplicated upon cancelling the dialog box, but the Editor would not close