Release build and debug build are now ABI compatible: the Py_DEBUG
define no longer implies Py_TRACE_REFS define which introduces the
only ABI incompatibility.

A new "./configure --with-trace-refs" build option is now required to
get Py_TRACE_REFS define which adds sys.getobjects() function and
PYTHONDUMPREFS environment variable.

Changes:

* Add ./configure --with-trace-refs
* Py_DEBUG no longer implies Py_TRACE_REFS

Add myself to the codeowners file as I would like to
be automatically added as a reviewer for PRs that touch
that component.

Fix the multiprocessing.semaphore_tracker so it is reused by child processes.

This is meant as a stub, during the PyCon sprints we can iterate.

Py_InitializeEx() now uses a runtime variable passed to subfunctions,
rather than working directly on the global variable _PyRuntime.

Add 'runtime' parameter to _PyCoreConfig_Write(), _PySys_Create(),
_PySys_InitMain(), _PyGILState_Init(),
emit_stderr_warning_for_legacy_locale() and other subfunctions.

* Add a 'runtime' variable to Py_FinalizeEx() rather than working
  directly on the global variable _PyRuntime
* Add a 'runtime' parameter to _PyGC_Fini(), _PyGILState_Fini()
  and call_ll_exitfuncs()

* document relative imports

* 📜🤖 Added by blurb_it.

* fix indentation error

* remove indentation

* Document relative imports

* Document relative imports

* remove from ...package

* Document relative imports

* remove trailing space

* Document relative imports

* Document relative imports

The PyOS_AfterFork_Child() function now pass a 'runtime' parameter to
subfunctions.

* Fix _PyRuntimeState_ReInitThreads(): use the correct memory allocator
* Add runtime parameter to _PyRuntimeState_ReInitThreads(),
  _PyGILState_Reinit() and _PyInterpreterState_DeleteExceptMain()
* Move _PyGILState_Reinit() to the internal C API.

* Add 'runtime' parameter to _PyThreadState_Init()
* Add 'gilstate' parameter to _PyGILState_NoteThreadState()
* Move _PyThreadState_Init() and _PyThreadState_DeleteExcept()
   to the internal C API.

"./configure --with-pymalloc" no longer adds the "m" flag to SOABI
(sys.implementation.cache_tag).

Enabling or disabling pymalloc has no impact on the ABI.

Change test_time.test_monotonic() to test only the lower bound of elapsed time
after a sleep command rather than the upper bound. This prevents unnecessary
test failures on slow buildbots. Patch by Victor Stinner.

xlc compiler doesn't support "-D define" flag only "-Ddefine".

Co-authored-by: Felipe <felipe.nospam.ochoa@gmail.com>

"sychronization" -> "synchronization"