CoverageValidator does not detect gap if tolerance is too large

The CoverageValidator may not detect narrow gaps if the gap tolerance is large relative to the input geometries. This is not ideal, since gaps may go undetected when using a tolerance that can detect large gaps.

Example

This is an extract from a dataset with much larger extent (so that a gap tolerance of say 1 seemed reasonable). The geometries contain a gap which is very narrow, between relatively short segments.

GEOMETRYCOLLECTION (
  POLYGON ((1.4021184536698854 1.655211920135038, 1.4021184539862759 1.6552119201560487, 1.4021299999999997 1.6559219999999968, 1.4021410000000003 1.6566259999999957, 1.4021410000000003 1.658296, 1.406 1.654, 1.4021184536698854 1.655211920135038)), 
  POLYGON ((1.406 1.654, 1.4 1.65, 1.4021410000000003 1.658296, 1.4021410000000003 1.6566259999999957, 1.4021365939839114 1.6563440149706494, 1.4021299996998664 1.6559220002002917, 1.4021184536698854 1.655211920135038, 1.406 1.654)))

Using a gap tolerance of 0.00001 detects the gap, but larger tolerances do not.

Start with CoverageValidator and reproduce the issue using the supplied GEOMETRYCOLLECTION, first with a gap tolerance of 0.00001 and then with larger tolerances. Trace how the tolerance is applied when checking the narrow gap; done means the gap remains detectable without losing the ability to detect larger gaps.