Update pytest config

* Move settings into pyproject.toml
* Set testpaths to avoid the "please monkey-patch earlier" warning from
  gevent (caused by pytest importing unnecessary files, including one
  that imported requests somewhere)

Author: prandla

pyproject.toml

@@ -74,3 +74,7 @@ devel = [
 [build-system]
 requires = ["setuptools>=80,<81", "babel==2.12.1"]
 build-backend = "setuptools.build_meta"
+
+[tool.pytest.ini_options]
+python_files = ["test_*.py", "*_test.py", "*Test.py"]
+testpaths = ["cmstestsuite/unit_tests"]