Bump pydantic from 2.4.2 to 2.12.3

Bumps [pydantic](https://github.com/pydantic/pydantic) from 2.4.2 to 2.12.3.
- [Release notes](https://github.com/pydantic/pydantic/releases)
- [Changelog](https://github.com/pydantic/pydantic/blob/main/HISTORY.md)
- [Commits](pydantic/pydantic@v2.4.2...v2.12.3)

---
updated-dependencies:
- dependency-name: pydantic
  dependency-version: 2.12.3
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

ka-chat-bot/requirements.txt

@@ -1,6 +1,6 @@
 fastapi==0.104.1
 uvicorn==0.24.0
-pydantic==2.4.2
+pydantic==2.12.3
 python-dotenv==1.0.0
 databricks-sdk==0.12.0
 aiofiles==23.2.1