Bump litellm from 1.39.5 to 1.40.0 (#2256)

Bumps [litellm](https://github.com/BerriAI/litellm) from 1.39.5 to 1.40.0.
- [Release notes](https://github.com/BerriAI/litellm/releases)
- [Commits](BerriAI/litellm@v1.39.5...v1.40.0)

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

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

Author: dependabot[bot]