build(deps-dev): update pytest-asyncio requirement (#903)

Updates the requirements on [pytest-asyncio](https://github.com/pytest-dev/pytest-asyncio) to permit the latest version.
- [Release notes](https://github.com/pytest-dev/pytest-asyncio/releases)
- [Commits](https://github.com/pytest-dev/pytest-asyncio/compare/v0.23.0...v1.4.0)

---
updated-dependencies:
- dependency-name: pytest-asyncio
  dependency-version: 1.4.0
  dependency-type: direct:development
...

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

requirements-dev.txt

@@ -4,7 +4,7 @@
 # Testing
 pytest>=8.0.0
 pytest-cov>=4.1.0
-pytest-asyncio>=0.23.0
+pytest-asyncio>=1.4.0
 pytest-mock>=3.12.0
 pytest-timeout>=2.3.0  # Per-test timeout enforcement to prevent CI hangs
 httpx>=0.26.0  # For async test client