How to reproduce it:
1. Open the user's attached project "InputActionsUIBug.zip"
2. Load the "SampleScene" Scene
3. Select a "GameObject" in the Hierarchy window
4. In the Inspector window, assign an "InputSystemUI" GameObject to the Player Input component's UI Input Module field
5. Click on the "Fix UI Input Module" button
6. In the Hierarchy view, select an "InputSystemUI" and observe the Input System UI Input Module properties
7. Enter the Play Mode
8. Click on the button in the Game view
9. Observe the button behavior

Expected result: Input System UI Input Module's Left Click value is changed to "None", but the Button in the Game view is clickable
Actual result: Input System UI Input Module's Left Click value remains, and the Button in the Game view is clickable

Reproducible with: 1.0.0-preview.5 (2019.4.22f1), 1.1.0-preview.3 (2019.4.22f1, 2020.3.1f1, 2021.1.0f1, 2021.2.0a10)
Not reproducible with: 1.0.0-preview.4 (2019.4.22f1)
Could not test with: 2018.4.33f1 - due to errors

Notes:
- After setting the Left Click value from "None" to another value and then returning it to "None", the button will become unresponsive