Fix bugs

[tastelikefeet]

PR type

• Bug Fix
• New Feature
• Document Updates
• More Models or Datasets Support

PR information

Write the detail information belongs to this PR.

Experiment results

Paste your experiment result here(if needed).

[gemini-code-assist]

Code Review

This pull request introduces a GRPO training script for the GSM8K dataset using Ray, incorporating a brevity reward mechanism to promote concise reasoning. It also adds a patch to the Megatron PEFT implementation to disable merge checks. Key feedback includes correcting the log probability extraction logic for vLLM outputs, moving initialization calls into the main function to prevent side effects, and optimizing performance by instantiating reward functions outside the training loop. Additionally, the commented-out LoRA adapter configuration should be addressed to ensure the intended training behavior.