gh-98257: Make _PyEval_SetTrace() reentrant

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Make sys.setprofile() and sys.settrace() functions reentrant. They can no long fail with: RuntimeError("Cannot install a trace function while another trace function is being installed").

Make _PyEval_SetTrace() and _PyEval_SetProfile() functions reentrant, rather than detecting and rejecting reentrant calls. Only delete the reference to function arguments once the new function is fully set, when a reentrant call is safe. Call also _PySys_Audit() earlier.

• Issue: _PyEval_SetTrace() fails with RuntimeError: Cannot install a trace function while another trace function is being installed #98257

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@markshannon @pablogsal: Would you mind to review this change?

The reentrant call introduced by the commit 40d81fd to fix gh-94510:

commit 40d81fd63b46cf998880ce3bf3e5cb42bc3199c1
Author: Pablo Galindo Salgado <Pablogsal@gmail.com>
Date:   Tue Jul 5 19:18:47 2022 +0100

    gh-94510: Raise on re-entrant calls to sys.setprofile and sys.settrace (GH-94511)
    
    Co-authored-by: Łukasz Langa <lukasz@langa.pl>

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This change fix #98257 on my Linux machine (without this fix, it takes less than a minute to reproduce it). I interrupted the test after 10 min:

$ ./python -m test test_import -m test_concurrency -j50 -F --fail-env-changed  
(...)
0:09:58 load avg: 51.58 [4904] test_import passed
0:09:58 load avg: 51.58 [4905] test_import passed
0:09:58 load avg: 51.58 [4906] test_import passed
0:09:58 load avg: 51.58 [4907] test_import passed
0:09:58 load avg: 51.58 [4908] test_import passed
0:09:58 load avg: 51.58 [4909] test_import passed
0:09:58 load avg: 51.58 [4910] test_import passed
0:09:58 load avg: 51.58 [4911] test_import passed
^C

I don't see any refleak regression:

$ ./python -m test test_sys_setprofile test_sys_settrace test_import -j3 -R 3:3
(...)
All 3 tests OK.

[ericsnowcurrently]

CC @brandtbucher