Document extractor node incorrectly handles doc and ppt files

[AugNSo]

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Dify version

0.15.1

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

1. Correctly set up ETL_TYPE as Unstructured
2. Build a workflow that contains document extractor node
3. Upload doc/ppt files

✔️ Expected Behavior

No response

❌ Actual Behavior

No response