build(deps): Bump pyautogen from 0.2.27 to 0.2.28

Bumps [pyautogen](https://github.com/microsoft/autogen) from 0.2.27 to 0.2.28.
- [Release notes](https://github.com/microsoft/autogen/releases)
- [Commits](microsoft/autogen@v0.2.27...v0.2.28)

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

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

requirements.txt

@@ -1,7 +1,7 @@
 pytest
 pytest-asyncio
 pytest-mock
-pyautogen==0.2.27
+pyautogen==0.2.28
 matplotlib
 scikit-learn
 tensorboard