update setup.py to also exclude python 3.12

Author: jonwzheng

setup.py

@@ -146,7 +146,8 @@
     author='William H. Green and the RMG Team',
     author_email='rmg_dev@mit.edu',
     url='http://reactionmechanismgenerator.github.io',
-    python_requires='>=3.9,<3.13',
+    python_requires='>=3.9,<3.12',
+
     packages=find_packages(where='.', include=["rmgpy*"]) + find_packages(where='.', include=["arkane*"]),
     scripts=scripts,
     entry_points={