Fix GelSight Mini render data path

[kellyguo11]

Description

Point GELSIGHT_MINI_CFG at the published gelsight_r15_data render-data
directory. The previous gs_mini_data background and calibration URLs return
404, causing GelSight Mini renderer initialization to fail with
FileNotFoundError.

This change preserves the existing public configuration symbol and makes its
background resolve to:

IsaacLab/TacSL/gelsight_r15_data/bg.jpg

No new dependencies are required.

Fixes #6182

Type of change

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

Screenshots

Not applicable.

Validation

• Confirmed the regression test fails with the old gs_mini_data/bg.jpg path.
• isaaclab.bat -p -m pytest source/isaaclab_assets/test/test_gelsight.py -q
  (1 passed; one unrelated existing deprecation warning)
• isaaclab.bat -p tools/changelog/cli.py check develop
• isaaclab.bat -f

Checklist

• I have read and understood the contribution guidelines.
• I have run the pre-commit checks with isaaclab.bat -f.
• Documentation changes are not required for this configuration correction.
• My changes generate no new warnings.
• I have added a regression test that proves the fix is effective.
• I have added a changelog fragment for isaaclab_assets.
• My name already exists in CONTRIBUTORS.md.

[isaaclab-review-bot]

Isaac Lab Review Bot

No material issues were identified in the reviewed diff.

• Design and architecture: No material concerns.
• API: No material concerns.
• Implementation: No material concerns.

Ship it. No actionable findings were identified in the reviewed diff.

Conservative automated review; human maintainers own approval decisions.

[greptile-apps]

Test only checks path text

This assertion only restates the configured path string, so it remains green when the referenced resource cannot be resolved or used during GelSight renderer initialization. Exercise resource resolution or renderer initialization to cover the reported regression.

Knowledge Base Used: Isaac Lab Assets and Contrib Extensions

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

[greptile-apps]

Greptile Summary

Corrects the GelSight Mini render-data directory and adds regression coverage.

• Reuses the published gelsight_r15_data directory in GELSIGHT_MINI_CFG.
• Adds a test asserting the resulting background-relative path.
• Adds an isaaclab_assets changelog fragment.

Confidence Score: 4/5

The PR appears safe to merge, with the non-blocking caveat that its regression test does not verify the resource-resolution failure it is intended to prevent.

The configuration now references the intended published directory, but the test can pass without proving that the background is retrievable and usable by the renderer.

Files Needing Attention: source/isaaclab_assets/test/test_gelsight.py

Important Files Changed

Filename	Overview
source/isaaclab_assets/isaaclab_assets/sensors/gelsight.py	Updates the GelSight Mini configuration to reference the published render-data directory while preserving its public symbol and other parameters.
source/isaaclab_assets/test/test_gelsight.py	Adds path-level regression coverage, but does not exercise resource resolution or renderer initialization.
source/isaaclab_assets/changelog.d/kellyguo11-fix-gelsight-mini-background-path.rst	Documents the corrected GelSight Mini render-data configuration.

_{Reviews (1): Last reviewed commit: "Fix GelSight Mini render data path" | Re-trigger Greptile}