chore(deps-dev): update httpx2 requirement from >=2.9.0 to >=2.10.0

Updates the requirements on [httpx2](https://github.com/pydantic/httpx2) to permit the latest version.
- [Release notes](https://github.com/pydantic/httpx2/releases)
- [Changelog](https://github.com/pydantic/httpx2/blob/main/src/httpx2/CHANGELOG.md)
- [Commits](pydantic/httpx2@v2.9.0...v2.10.0)

---
updated-dependencies:
- dependency-name: httpx2
  dependency-version: 2.10.0
  dependency-type: direct:development
...

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

Author: dependabot[bot]

requirements-dev.txt

@@ -7,4 +7,4 @@ PyYAML>=6.0
 # starlette's TestClient (used by tests/test_api.py) requires httpx2;
 # it falls back to httpx with a deprecation warning, and raises if neither
 # is installed. Nothing else in this file or api/requirements.txt pulls it in.
-httpx2>=2.9.0
+httpx2>=2.10.0