Bump python-dotenv from 1.1.1 to 1.2.1 (#129)

Bumps [python-dotenv](https://github.com/theskumar/python-dotenv) from 1.1.1 to 1.2.1.
- [Release notes](https://github.com/theskumar/python-dotenv/releases)
- [Changelog](https://github.com/theskumar/python-dotenv/blob/main/CHANGELOG.md)
- [Commits](theskumar/python-dotenv@v1.1.1...v1.2.1)

---
updated-dependencies:
- dependency-name: python-dotenv
  dependency-version: 1.2.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

requirements.txt

@@ -3,6 +3,6 @@ langchain-couchbase==0.4.0
 langchain-community==0.3.31
 langchain-openai==0.3.33
 langsmith==0.4.39
-python-dotenv==1.1.1
+python-dotenv==1.2.1
 streamlit==1.51.0
 tqdm==4.67.1