Comment 8 for bug 1740633

It's definitely not high priority in any case, I see how it comes about from the overlap between the different thermal relief zones.

If we ever get thermal reliefs working for arbitrary pad shapes, then I think the way to solve this is to have the zone fill algo merge overlapping pads into one big "custom" pad for the sake of calculating the fill. Until then, I guess just don't set the smaller holes to have thermal reliefs.