gh-111863: Rename Py_NOGIL to Py_GIL_DISABLED

[hugovk]

A suggestion for gh-111863, following the pattern of the --disable-gil flag.

cc @colesbury

[pitrou]

Then I would suggest Py_GIL_DISABLED (using a noun + adjective, rather than a verb, for a constant).

[colesbury]

Thanks @hugovk. I would like some comment first from the Python steering council about the preferred name so that:

1. We don't need to change it again in the future.
2. We don't spend too much time bikeshedding the name.

Beyond that, we'll also need to change pypa/packaging as it uses sysconfig.get_config_var("Py_NOGIL"), which comes from the macro defined in configure.

[gpshead]

The SC threw our xkcd-randomized dart at the dartboard of bikeshed names: it landed on Py_GIL_DISABLED.

[hugovk]

Thanks, updated to use Py_GIL_DISABLED.

[Yhg1s]

This created a file in Misc/NEWS.d/next/C_API, presumably by accident. The actual directory should be Misc/NEWS.d/next/"C API" (a space instead of an underscore). Was the blurb file created by hand, or is this a bug in blurb or blurb-it?