Bump nltk

Bumps [nltk](https://github.com/nltk/nltk) from 3.9.1 to 3.9.4.
- [Changelog](https://github.com/nltk/nltk/blob/develop/ChangeLog)
- [Commits](nltk/nltk@3.9.1...3.9.4)

---
updated-dependencies:
- dependency-name: nltk
  dependency-version: 3.9.4
  dependency-type: direct:production
...

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Author: dependabot[bot]

cloud-infrastructure/compute-including-hpc/ai-infra-gpu/ai-infrastructure/rag-langchain-vllm-mistral/files/requirements.txt

@@ -122,7 +122,7 @@ nest-asyncio==1.6.0
 networkx==3.4.2
 newspaper3k==0.2.8
 ninja==1.11.1.4
-nltk==3.9.1
+nltk==3.9.4
 numba==0.61.0
 numpy==2.1.3
 nvidia-cublas-cu12==12.4.5.8