⬆ Bump pydantic from 2.11.7 to 2.11.9 in /backend (fastapi#1891)

Bumps [pydantic](https://github.com/pydantic/pydantic) from 2.11.7 to 2.11.9.
- [Release notes](https://github.com/pydantic/pydantic/releases)
- [Changelog](https://github.com/pydantic/pydantic/blob/v2.11.9/HISTORY.md)
- [Commits](pydantic/pydantic@v2.11.7...v2.11.9)

---
updated-dependencies:
- dependency-name: pydantic
  dependency-version: 2.11.9
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]