Fixes moving to cpu if needed in camera.py (#2176)

# Description

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I just add moving to cpu before casting to numpy. If it's already on cpu
then the change is armless.

Fixes #2175 

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## Type of change

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

---------

Signed-off-by: renaudponcelet <renaud.poncelet@gmail.com>
Signed-off-by: Kelly Guo <kellyg@nvidia.com>
Co-authored-by: Kelly Guo <kellyg@nvidia.com>

Author: renaudponcelet

CONTRIBUTORS.md

@@ -92,6 +92,7 @@ Guidelines for modifications:
 * Qian Wan
 * Qinxi Yu
 * Rafael Wiltz
+* Renaud Poncelet
 * René Zurbrügg
 * Ritvik Singh
 * Rosario Scalise

source/isaaclab/isaaclab/sensors/camera/camera.py

@@ -124,7 +124,7 @@ def __init__(self, cfg: CameraCfg):
             rot_offset = convert_camera_frame_orientation_convention(
                 rot, origin=self.cfg.offset.convention, target="opengl"
             )
-            rot_offset = rot_offset.squeeze(0).numpy()
+            rot_offset = rot_offset.squeeze(0).cpu().numpy()
             # ensure vertical aperture is set, otherwise replace with default for squared pixels
             if self.cfg.spawn.vertical_aperture is None:
                 self.cfg.spawn.vertical_aperture = self.cfg.spawn.horizontal_aperture * self.cfg.height / self.cfg.width