Bump langchain from 0.2.10 to 0.3.0

Bumps [langchain](https://github.com/langchain-ai/langchain) from 0.2.10 to 0.3.0.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](langchain-ai/langchain@langchain==0.2.10...langchain==0.3.0)

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

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

requirements.txt

@@ -2,7 +2,7 @@ fastapi==0.111.0
 uvicorn==0.30.1
 pydantic==1.10.15
 sse-starlette==2.1.0
-langchain==0.2.10
+langchain==0.3.0
 langchain-community==0.2.9
 transformers==4.41.2
 google-cloud-aiplatform==1.53.0