chore(deps): Update litellm requirement

Updates the requirements on [litellm](https://github.com/BerriAI/litellm) to permit the latest version.
- [Release notes](https://github.com/BerriAI/litellm/releases)
- [Commits](BerriAI/litellm@v1.57.3...v1.60.8)

---
updated-dependencies:
- dependency-name: litellm
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -12,7 +12,7 @@ dependencies = [
   "jinja2~=3.0",
   "PyYAML~=6.0",
   "jsonschema~=4.0",
-  "litellm>=1.57.3,<1.59.9",
+  "litellm>=1.57.3,<1.60.9",
   "termcolor~=2.0",
   "ipython~=8.0",
   "json-repair~=0.35",