fix: memory leak by pypdfium2 close(maybe) #11510

[yihong0618]

Summary

This patch fix a memory leak by updating the pypdfium2 version to latest. close #11510

how to trace the memory leak:

follow the article: https://pythonspeed.com/articles/python-server-memory-leaks/

1. using filprofiler
2. run the program python -m filprofiler run app.py
3. another program run times python -m pytest api/tests/integration_tests/workflow

the memory profile show almost all memory cost from pypdfium2

search the net found these:
facebookresearch/nougat#110
https://forum.patagames.com/posts/t805-Memory-Leak-in-PDFDocument-Load-when-Pdfium-FPDF-LoadCustomDocument-returns-an-IntPtr-Zero

try to update the pypdfium2 version to latest

https://pyoven.org/package/pypdfium2?tab=versions

than do the steps again
new memory profile looks normal

Tip

Close issue syntax: Fixes #<issue number> or Resolves #<issue number>, see documentation for more details.

Screenshots

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Checklist

Important

Please review the checklist below before submitting your pull request.

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods

[laipz8200]

LGTM