Add support for Python 3.12 and Django 4.2.

Review Request #13091 — Created June 1, 2023 and submitted — Latest diff uploaded


Django Evolution


This adds formal support for testing and installing on Python 3.12 and
with Django 4.2.

Python 3.12 requires a newer version of the bundled six in order to
import six.moves, but otherwise didn't require any changes.

Django 4.2 passes all unit tests, so we can begin enabling support for
installing alongside it. It's now in our classifiers along with Python
3.12, and enabled in our Django version range.

Tox has been updated to test these versions.

Unit tests for Django 1.6 through 4.2 pass.

Unit tests for Python 2.7 through 3.12 pass.

Ran combinations of the two, and they pass.