troubleshoot invalid distance error

[DanielJDufour]

Running the test of a million random points logs this warning

...\site-packages\shapely\measurement.py:72: RuntimeWarning: invalid value encountered in distance
  return lib.distance(a, b, **kwargs)

[DanielJDufour]

It doesn't seem to actually impact the results, but we should find out if there's a way to prevent this from happening as it lowers confidence in the package.