Bump langchain from 0.1.9 to 0.1.11

Bumps [langchain](https://github.com/langchain-ai/langchain) from 0.1.9 to 0.1.11.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](langchain-ai/langchain@v0.1.9...v0.1.11)

---
updated-dependencies:
- dependency-name: langchain
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements.txt

@@ -10,7 +10,7 @@ python-dotenv===1.0.1
 webdriver-manager===4.0.1
 fastapi===0.109.2
 uvicorn===0.27.1
-langchain===0.1.9
+langchain===0.1.11
 langchain-elasticsearch==0.1.0
 langchain-openai==0.0.8
 tiktoken==0.6.0