Declare support for Python 3.13

[edgarrmondragon]

What does this change

The first release candidate of Python 3.13 is around the corner (2024-07-30), this adds it to the test matrix and declares support in the project metadata.

What was wrong

Python 3.13 seems to be supported without any code changes, but this makes sure it's tested.

How this fixes it

• Adds PyPI trove classifier
• Adds 3.13 to the list of versions for actions/setup-python

[edgarrmondragon]

Tests are 🟢 over on my fork: https://github.com/edgarrmondragon/faker/actions/runs/9849708765

[edgarrmondragon]

Rebased and confirmed with tox -e py313 that tests pass.

[edgarrmondragon]

ping @fcurella 🙏

[fcurella]

Thank you!