Fixes typos in the interpolation test of Scipy library (#430)

# Description

Currently `test_scipy.py` fails with the following error:
```
======================================================================
ERROR: test_interpolation (test_scipy.TestScipyOperations)
Test scipy interpolation 2D method.
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/workspace/orbit/source/extensions/omni.isaac.orbit/test/deps/test_scipy.py", line 58, in test_interpolation
    func_RectBiVariate = interpolate.RectBivariateSpline(y, x, height_field_downsampled)
  File "/isaac-sim/exts/omni.pip.compute/pip_prebundle/scipy/interpolate/_fitpack2.py", line 1494, in __init__
    raise ValueError('x dimension of z must have same number of '
ValueError: x dimension of z must have same number of elements as x

----------------------------------------------------------------------
Ran 1 test in 0.003s

FAILED (errors=1)
There was an error running python
```
#426 changed the argument in `test_scipy.py` but did not change the
ordering to be the correct `(x,y)`. This fixes that.

## Type of change

- Bug fix (non-breaking change which fixes an issue)

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./orbit.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [x] I have run all the tests with `./orbit.sh --test` and they pass
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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source/extensions/omni.isaac.orbit/test/deps/test_scipy.py

@@ -51,19 +51,19 @@ class TestScipyOperations(unittest.TestCase):
         # interpolate the sampled heights to obtain the height field
         x_upsampled = np.linspace(0, size[0] * horizontal_scale, width_pixels)
         y_upsampled = np.linspace(0, size[1] * horizontal_scale, length_pixels)
-        # -- method 1: interp2d (this will be deprecated in the future 1.13 release)
+        # -- method 1: interp2d (this will be deprecated in the future 1.12 release)
         func_interp2d = interpolate.interp2d(y, x, height_field_downsampled, kind="cubic")
         z_upsampled_interp2d = func_interp2d(y_upsampled, x_upsampled)
         # -- method 2: RectBivariateSpline (alternate to interp2d)
-        func_RectBiVariate = interpolate.RectBivariateSpline(y, x, height_field_downsampled)
-        z_upsampled_RectBivariant = func_RectBiVariate(y_upsampled, x_upsampled)
+        func_RectBiVariate = interpolate.RectBivariateSpline(x, y, height_field_downsampled)
+        z_upsampled_RectBivariant = func_RectBiVariate(x_upsampled, y_upsampled)
         # -- method 3: RegularGridInterpolator (recommended from scipy but slow!)
         # Ref: https://github.com/scipy/scipy/issues/18010
         func_RegularGridInterpolator = interpolate.RegularGridInterpolator(
-            (y, x), height_field_downsampled, method="cubic"
+            (x, y), height_field_downsampled, method="cubic"
         )
-        yy_upsampled, xx_upsampled = np.meshgrid(y_upsampled, x_upsampled, indexing="ij", sparse=True)
-        z_upsampled_RegularGridInterpolator = func_RegularGridInterpolator((yy_upsampled, xx_upsampled))
+        xx_upsampled, yy_upsampled = np.meshgrid(x_upsampled, y_upsampled, indexing="ij", sparse=True)
+        z_upsampled_RegularGridInterpolator = func_RegularGridInterpolator((xx_upsampled, yy_upsampled))
 
         # check if the interpolated height field is the same as the sampled height field
         np.testing.assert_allclose(z_upsampled_interp2d, z_upsampled_RectBivariant, atol=1e-14)