GitHub Actions: Add free threading Python 3.14t to the testing

[cclauss]

Related to:

• feat: Include abiflags in version dectection (enabling 3.13t) #199

Description

GitHub Actions: Add free threading Python 3.14t to the testing

• https://www.python.org/downloads/release/python-3140/

Is there a way to make these two tests pass under free threading?

+ skip_if_free_threaded = pytest.mark.skipif(
+     sys.version_info >= (3, 13) and not sys._is_gil_enabled(),
+     reason="Fails on free threaded builds",
+ )

+ @skip_if_free_threaded
  def test_sunny_day_with_legacy_command(

  [ ... ]

+ @skip_if_free_threaded
  def test_sunny_day_with_run_command(

Expected Behavior

All tests continue to pass

@effigies, your review please.

[ymyzk]

Let me spend a bit more time to figure out how to support free threading in tox-gh-actions (related #199) and come back to this PR later. As Python 3.14 is already released, this is definitely a priority.

[effigies]

@effigies, your review please.

Sorry, I don't have any time to work on this at the moment.