Fix eval pp bug when do_train is false

[will-jl944]

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PR types

Bug fixes

PR changes

Models

Description

Wrapping model with fleet.distributed_model causes model losing _prepare_pipeline_inputs_func attribute.

[paddle-bot]

Thanks for your contribution!

[DesmonDay]

LGTM

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 50.35%. Comparing base (658bec2) to head (43a347f).
Report is 7 commits behind head on develop.

Files with missing lines	Patch %	Lines
paddlenlp/trainer/trainer.py	0.00%	3 Missing ⚠️

❌ Your patch check has failed because the patch coverage (0.00%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.
❌ Your project check has failed because the head coverage (50.35%) is below the target coverage (58.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop   #10012   +/-   ##
========================================
  Coverage    50.35%   50.35%           
========================================
  Files          756      756           
  Lines       121559   121562    +3     
========================================
+ Hits         61214    61216    +2     
- Misses       60345    60346    +1     

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[wtmlon]

LGTM