fix: IntersectionWith() to return a single point when a line tangent to the circle

Author: f-frhs

src/Spatial/Euclidean/Circle2D.cs

@@ -175,6 +175,7 @@ private double[] findParameterTs(Line2D line)
             var ts = solutions
                 .Where(z => z.IsReal())
                 .Select(z => z.Real)
+                .Distinct()
                 .ToArray();
             return ts;
         }