Fix Float32HFFTN test to call hfftn instead of hfft2

The test method was incorrectly calling fft.hfft2() instead of fft.hfftn(),
and using ihfft2() instead of ihfftn() for verification. Updated the TestOf
attribute to match the correct function being tested.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: alinpahontu2912

test/TorchSharpTest/TestTorchTensor.cs

@@ -7228,15 +7228,15 @@ public void Float64HFFT2()
         }
 
         [Fact]
-        [TestOf(nameof(fft.hfft2))]
+        [TestOf(nameof(fft.hfftn))]
         public void Float32HFFTN()
         {
             var input = torch.rand(new long[] { 5, 5, 5, 5 }, complex64);
-            var output = fft.hfft2(input);
+            var output = fft.hfftn(input);
             Assert.Equal(new long[] { 5, 5, 5, 8 }, output.shape);
             Assert.Equal(ScalarType.Float32, output.dtype);
 
-            var inverted = fft.ihfft2(output);
+            var inverted = fft.ihfftn(output);
             Assert.Equal(new long[] { 5, 5, 5, 5 }, inverted.shape);
             Assert.Equal(ScalarType.ComplexFloat32, inverted.dtype);
         }