Update the call and unit test for Splice due to changes in Magick.Native

Author: dlemstra

src/Magick.NET/MagickImage.CloneMutator.cs

@@ -656,7 +656,11 @@ public void Splice(IMagickGeometry geometry)
             => Splice(geometry, Gravity.Undefined);
 
         public void Splice(IMagickGeometry geometry, Gravity gravity)
-            => SetResult(NativeMagickImage.Splice(MagickRectangle.FromGeometry(geometry, (uint)NativeMagickImage.Width_Get(), (uint)NativeMagickImage.Height_Get()), gravity));
+        {
+            Throw.IfNull(geometry);
+
+            SetResult(NativeMagickImage.Splice(geometry.ToString(), gravity));
+        }
 
         public void Spread()
             => Spread(NativeMagickImage.Interpolate_Get(), 3);

src/Magick.NET/Native/MagickImage.cs

@@ -718,7 +718,7 @@ private unsafe sealed partial class NativeMagickImage : NativeInstance, INativeM
         public partial IntPtr SparseColor(Channels channel, SparseColorMethod method, double[] values, nuint length);
 
         [Throws]
-        public partial IntPtr Splice(MagickRectangle geometry, Gravity gravity);
+        public partial IntPtr Splice(string geometry, Gravity gravity);
 
         [Throws]
         public partial IntPtr Spread(PixelInterpolateMethod method, double radius);

tests/Magick.NET.Tests/MagickImageTests/TheSpliceMethod.cs

@@ -49,8 +49,8 @@ public void ShouldUseTheGravityWhenSplicingTheBackgroundColorIntoTheImage()
 
             Assert.Equal(296U, image.Width);
             Assert.Equal(87U, image.Height);
-            ColorAssert.Equal(MagickColors.Fuchsia, image, 110, 60);
-            ColorAssert.Equal(new MagickColor("#0000"), image, 109, 59);
+            ColorAssert.Equal(MagickColors.Fuchsia, image, 248, 83);
+            ColorAssert.Equal(new MagickColor("#0000"), image, 247, 82);
         }
     }
 }