MAINT: 3.12 support

[tylerjereddy]

• a few adjustments to pyproject.toml to allow for pip install -v . followed by python -m pytest --pyargs darshan -n 32 to pass the full suite locally on x86_64 Linux with Python 3.12.0rc3, given that the final release of Python 3.12.0 is about a week away I think

• changing the version of setuptools may break the developer experience with "editable" installs, since I recall pinning it a while back for that reason, but I think supporting isolated wheel builds/install with 3.12.0 should likely take priority

• some of the metadata updates to pyproject.toml are apparently newly-required fields that must be present (pip install -v . fails otherwise)

• perhaps we can delay adding 3.12 to the CI testing until the final release, though GHA does have the RC available if we want it

[skip cirrus]

[tylerjereddy]

Needed to add a few shims for FutureWarnings from newer pandas release as well.

[tylerjereddy]

There's still a type hinting error (mypy) to deal with: darshan/experimental/plots/plot_io_cost.py:180: error: "_AxesBase" has no attribute "legend" [attr-defined]

Maybe because of a newer matplotlib, I won't get to that today though.

[shanedsnyder]

I think the changes look good, thanks! The pandas future warning looks to be popping up elsewhere (#961, #963 ), so will be good to have that resolved.

Any objections to just adding 3.12 to the CI here to see what happens?

Aside from the outstanding CI error related to mypy, my only other suggestion is to add mention of the new place we need to maintain our version number (pyproject.toml) to RELEASE-CHECKLIST-PyDarshan.txt so we have a reminder as part of the release process.

[tylerjereddy]

Latest revisions pushed in are summarized below, but we'll have to wait and see if CI is happy:

* `plot_io_cost` now sets legend properties via the
raw axis object instead of via the twinned object (fixes
a `mypy` complaint)

* add Python `3.12` to the main CI matrix based on
reviewer feedback

* update release checklist to reflect version
number now maintained in `pyproject.toml` as well

[shanedsnyder]

Awesome, looks like everything is working here now, including the new 3.12 tests.

I'll go ahead and merge. Thanks!