Bump langchain from 0.2.11 to 0.2.12 (#4401)

Bumps [langchain](https://github.com/langchain-ai/langchain) from 0.2.11 to 0.2.12.
- [Release notes](https://github.com/langchain-ai/langchain/releases)
- [Commits](https://github.com/langchain-ai/langchain/compare/langchain==0.2.11...langchain==0.2.12)

---
updated-dependencies:
- dependency-name: langchain
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements.txt

@@ -2,7 +2,7 @@ amqp==5.2.0
 beautifulsoup4==4.12.3
 boto3==1.34.151
 imbalanced-learn==0.12.3
-langchain==0.2.11
+langchain==0.2.12
 langchain-community==0.2.10
 langchain-openai==0.1.19
 libmozdata==0.2.6