[AutoParallel] fix trainer offload opt params bug

[waliwali777]

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# Install and register `pre-commit` in the project folder
pip install pre-commit && pre-commit install

# Process previous code files separately
pre-commit run --file XXXX.py

• Add test cases into tests folder. If there are codecov issues, please add tests cases first.

PR types

Bug fixes

PR changes

APIs

Description

修复 opt 参数卸载 bug，目前只在非自动并行下启动

[paddle-bot]

Thanks for your contribution!

[codecov-commenter]

Codecov Report

❌ Patch coverage is 42.85714% with 4 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (develop@26d3e2c). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
paddleformers/trainer/trainer.py	42.85%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             develop    #2944   +/-   ##
==========================================
  Coverage           ?   31.41%           
==========================================
  Files              ?      420           
  Lines              ?    68464           
  Branches           ?        0           
==========================================
  Hits               ?    21509           
  Misses             ?    46955           
  Partials           ?        0           

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[liym27]

LGTM

[nepeplwu]

LGTM