gh-142225: Fix PyABIInfo_VAR macro

[StanFromIreland]

Include/modsupport.h:143:29: error: '_PyABIInfo_DEFAULT' undeclared here (not in a function); did you mean 'PyABIInfo_STABLE'?
  143 |     static PyABIInfo NAME = _PyABIInfo_DEFAULT;
      |                             ^~~~~~~~~~~~~~~~~~
/tmp/test.c:4:1: note: in expansion of macro 'PyABIInfo_VAR'
    4 | PyABIInfo_VAR(test_abi_info);
      | ^~~~~~~~~~~~~

• Issue: PyABIInfo_VAR broken #142225

[encukou]

Thanks!
I noticed recently, but got caught up in writing tests/docs.
Let's get the fix in; tests will follow.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot s390x Fedora Stable 3.x (tier-3) has failed when building commit fb404ab.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1636/builds/1654) and take a look at the build logs.
4. Check if the failure is related to this commit (fb404ab) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1636/builds/1654

Failed tests:

• test_profiling

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-s390x/build/Lib/test/test_profiling/test_sampling_profiler/test_modes.py", line 163, in test_cpu_mode_integration_filtering
    with test_subprocess(cpu_vs_idle_script) as subproc:
         ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-s390x/build/Lib/contextlib.py", line 141, in __enter__
    return next(self.gen)
  File "/home/buildbot/buildarea/3.x.cstratak-fedora-stable-s390x/build/Lib/test/test_profiling/test_sampling_profiler/helpers.py", line 85, in test_subprocess
    raise RuntimeError(
        f"Unexpected response from subprocess: {response!r}"
    )
RuntimeError: Unexpected response from subprocess: b'readythreads_ready'