Fixes vertical aperture check in RayCasterCamera test (#2020)

# Description

The RayCasterCamera test checks that the vertical aperture should match
the value specified in the config. However, the config's vertical
aperture is not set. This PR updates the test to check against the
default computed vertical aperture value instead.

## Type of change

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applicable. -->

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

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.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
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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source/isaaclab/test/sensors/test_ray_caster_camera.py

@@ -572,7 +572,11 @@ class TestWarpCamera(unittest.TestCase):
         )
         torch.testing.assert_close(
             camera_usd._sensor_prims[0].GetVerticalApertureAttr().Get(),
-            camera_cfg_warp.pattern_cfg.vertical_aperture,
+            (
+                camera_cfg_warp.pattern_cfg.horizontal_aperture
+                * camera_cfg_warp.pattern_cfg.height
+                / camera_cfg_warp.pattern_cfg.width
+            ),
         )
 
         # check image data