fix: bound pytest to <10 to prevent unexpected major version upgrades

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Co-authored-by: fabiocaccamo <1035294+fabiocaccamo@users.noreply.github.com>

Author: Copilot

requirements-test.txt

@@ -2,6 +2,6 @@
 coverage == 7.13.*
 mypy == 1.20.*
 pre-commit == 4.5.*
-pytest>=9.0.3
+pytest>=9.0.3,<10
 pytest-cov == 7.1.*
 tox == 4.53.*