Scroll bar thickness is unaffected when set below 4

Scroll bar thickness is unaffected when set below 4. There appears to be a minimum size in place that prevents the scroll bar from being set to a size lower than 4

1. Open the editor
2. Create a new widget blueprint
3. Add a scroll box to the widget designer tab
4. Add enough buttons to the scroll box to show the scroll bar
5. Set the scroll bar thickness to 4 and then set it lower than for (1 for this test was used)

Result: The scroll bar thickness appears unaffected by values less than 4
Expected: The scroll bar thickness would lessen as the number is set below 4