Added Python 3.13 to pyproject.toml in classifiers

[dhelms33]

• closes #DOC: Pandas 2.2.3 pyproject.toml missing "Python 3.13" in classifiers -- but Pandas supports this Python version #59978- added "'Programming Language :: Python :: 3.13'," to pyproject.toml
• tests not needed for updating pyproject.toml in classifiers
• In the middle of installing code checks. If necessary will reinstall and resub my ticket if necessary
• New type annotations not necessary
• Not adding new feature

[mroeschke]

Thanks for the PR but as you mentioned in #59978 (comment) there's already an open PR for this issue so closing