GH-103545: Add macOS specific constants for os.setpriority to os

[ronaldoussoren]

This adds a number of PRIO_DARWIN_* constants to the os module for use with os.setpriority.

• Issue: expose platform-specific PRIO_DARWIN_* constants for core type selection on macOS in os module. #103545

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📚 Documentation preview 📚: https://cpython-previews--104606.org.readthedocs.build/

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Arch Linux TraceRefs 3.x has failed when building commit 616fcad.

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/all/#builders/484/builds/3337) and take a look at the build logs.
4. Check if the failure is related to this commit (616fcad) 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/all/#builders/484/builds/3337

Failed tests:

• test__xxsubinterpreters

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

==

Click to see traceback logs

Traceback (most recent call last):
Warning --   File "/buildbot/buildarea/3.x.pablogsal-arch-x86_64/build/Lib/test/libregrtest/runtest_mp.py", line 342, in run
Warning --     mp_result = self._runtest(test_name)
Warning --                 ^^^^^^^^^^^^^^^^^^^^^^^^
Warning --   File "/buildbot/buildarea/3.x.pablogsal-arch-x86_64/build/Lib/test/libregrtest/runtest_mp.py", line 301, in _runtest
Warning --     stdout = stdout_fh.read().strip()
Warning --              ^^^^^^^^^^^^^^^^
Warning --   File "/buildbot/buildarea/3.x.pablogsal-arch-x86_64/build/Lib/codecs.py", line 322, in decode
Warning --     (result, consumed) = self._buffer_decode(data, self.errors, final)
Warning --                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Warning -- UnicodeDecodeError: 'utf-8' codec can't decode byte 0xfd in position 590: invalid start byte
Kill <TestWorkerProcess #1 running test=test_urllibnet pid=645204 time=1.9 sec> process group