Fixes memory leak in SDF calculation - warp doesn't free memory (#2680)

# Description

Thanks to Matteo Grimaldi, Saleh Nabi and Wonju Lee for identifying the
source of this memory leak.

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Add garbage collector calls since warp doesn't handle well the free
memory.

Fixes #2679 

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## Type of change

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applicable. -->

- Bug fix

## Screenshots

Before this change - the experiment hasn't been completed on 64GB RAM
machines.
After  this change it requires less than 12GB RAM.
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![Screenshot 2025-06-12 at 18 31
38](https://github.com/user-attachments/assets/695de828-2f9d-4714-aae3-5d9831ae6e77)

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] 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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---------
Signed-off-by: David <ddleon@outlook.co.il>
Signed-off-by: Kelly Guo <kellyguo123@hotmail.com>
Co-authored-by: Kelly Guo <kellyguo123@hotmail.com>

CONTRIBUTORS.md

@@ -122,6 +122,7 @@ Guidelines for modifications:
 * Zhengyu Zhang
 * Ziqi Fan
 * Zoe McCarthy
+* David Leon
 
 ## Acknowledgements
 

source/isaaclab_tasks/isaaclab_tasks/direct/automate/industreal_algo_utils.py

@@ -38,6 +38,8 @@ Contains functions that implement Simulation-Aware Policy Update (SAPU), SDF-Bas
 Not intended to be executed as a standalone script.
 """
 
+# Force garbage collection for large arrays
+import gc
 import numpy as np
 import os
 
@@ -150,8 +152,14 @@ def get_sdf_reward(
 
         sdf_reward[i] = torch.mean(sdf_dist)
 
+        del mesh_copy
+        del mesh_points
+        del mesh_indices
+        del sampled_points
+
     sdf_reward = -torch.log(sdf_reward)
 
+    gc.collect()  # Force garbage collection to free memory
     return sdf_reward