Update pytest requirement from >=8.0 to >=9.0.3

Updates the requirements on [pytest](https://github.com/pytest-dev/pytest) to permit the latest version.
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@8.0.0...9.0.3)

---
updated-dependencies:
- dependency-name: pytest
  dependency-version: 9.0.3
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -4,5 +4,5 @@ uvicorn==0.48.0
 python-dotenv==1.2.2
 mando==0.8.2
 # --- dev / CI only -------------------------------------------------
-pytest>=8.0
+pytest>=9.0.3
 pytest-asyncio>=0.23