"PolygonGeometry.ClosestPoint" not returning perimeter point when overlapped.

Steps to reproduce:

1. Create a PolygonGeometry (with or without a radius)
2. Call PolygonGeometry.Closest point with the point overlapping the geometry

Actual results: The closest point is always the input point.

Expected results: The closest point should always be on the geometry perimeter.

Reported on Discussions: https://discussions.unity.com/t/geometry-closestpoint-calculations-are-inconsistent-between-shape-types/1709349