fix(security): bump pytest >=9.0.3 in examples/python (ENG-14486)

- pytest 8.4.2 → 9.0.3 (CVE-2025-71176 — local privilege escalation via /tmp/pytest-of-{user} directory)
- Bumped python constraint ^3.9 → ^3.10 (requests >=2.33.0 and pytest >=9.0.3 both require Python >=3.10; 3.9 support was already broken)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: andriy-sudo