Update dependency pytest to v9 (#355)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

pyproject.toml

@@ -31,7 +31,7 @@ dev-dependencies= [
     "black==25.11.0",
     "pycodestyle==2.14.0",
     "mypy==1.18.2",
-    "pytest==8.4.2",
+    "pytest==9.0.1",
     "pytest-cov==7.0.0",
     "sphinxcontrib-autoprogram==0.1.9",
     "types-docutils==0.20.0.20240310",