### Checklist Before Starting

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### What does this PR do?

> Add one-line overview of what this PR aims to achieve or accomplish. 

Sorry, I found in my tests that with the latest branch and the
AMD-modified version of Ray
(https://github.com/ray-project/ray/pull/53531/files), it’s no longer
necessary to override HIP_VISIBLE_DEVICES here. For the sake of keeping
the code clean, could you please revert this change?

### High-Level Design

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### Specific Changes

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### API

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### Usage Example

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```python
# Add code snippet or script demonstrating how to use this 
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### Additional Info.

- **Issue Number**: Fixes issue # or discussion # if any.
- **Training**: [Note which backend this PR will affect: FSDP, Megatron,
both, or none]
- **Inference**: [Note which backend this PR will affect: vLLM, SGLang,
both, or none]

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