Previously, (v7), the NPTH had a too-large clearance. This affected the
fill so that there was no island. In v8, at some point, NPTH had zero
clearance, which was definitely incorrect but also did not create an
island.
Correcting this to have the appropriate clearance between copper and
NPTH results in one almost island that has a neck and is appropriately
caught by the copper connection check.