Bump datasets from 3.6.0 to 4.8.5 in /api

Bumps [datasets](https://github.com/huggingface/datasets) from 3.6.0 to 4.8.5.
- [Release notes](https://github.com/huggingface/datasets/releases)
- [Commits](huggingface/datasets@3.6.0...4.8.5)

---
updated-dependencies:
- dependency-name: datasets
  dependency-version: 4.8.5
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

api/pyproject.toml

@@ -15,7 +15,7 @@ dependencies = [
   "asyncpg==0.30.0",
   "alembic==1.17.2",
   "boto3==1.40.70",
-  "datasets==3.6.0",
+  "datasets==4.8.5",
   "fastapi==0.115.12",
   "fastapi-users[sqlalchemy,oauth]==15.0.5",
   "httpx-oauth==0.16.1",