text: Title: [Bug] fix gemma-2-2b-it-FP8 accuracy
  Body: ### Checklist
  
  - [ ] 1. I have searched related issues but cannot get the expected help.
  - [ ] 2. The bug has not been fixed in the latest version.
  - [ ] 3. Please note that if the bug-related issue you submitted lacks corresponding environment info and a minimal reproducible demo, it will be challenging for us to reproduce and resolve the issue, reducing the likelihood of receiving feedback.
  - [ ] 4. If the issue you raised is not a bug but a question, please raise a discussion at https://github.com/sgl-project/sglang/discussions/new/choose Otherwise, it will be closed.
  - [ ] 5. Please use English, otherwise it will be closed.
  
  ### Describe the bug
  
  ```
  neuralmagic/gemma-2-2b-it-FP8 | 0.512 | 0.6
  ```
  https://github.com/sgl-project/sglang/actions/runs/13800885290
  
  ### Reproduction
  
  N/A
  
  ### Environment
  
  N/A