bpo-40137: Add pycore_moduleobject.h internal header (GH-25507)

Add pycore_moduleobject.h internal header file with static inline
functions to access module members:

* _PyModule_GetDict()
* _PyModule_GetDef()
* _PyModule_GetState()

These functions don't check at runtime if their argument has a valid
type and can be inlined even if Python is not built with LTO.

_PyType_GetModuleByDef() uses _PyModule_GetDef().

Replace PyModule_GetState() with _PyModule_GetState() in the
extension modules, considered as performance sensitive:

* _abc
* _functools
* _operator
* _pickle
* _queue
* _random
* _sre
* _struct
* _thread
* _winapi
* array
* posix

The following extensions are now built with the Py_BUILD_CORE_MODULE
macro defined, to be able to use the internal pycore_moduleobject.h
header: _abc, array, _operator, _queue, _sre, _struct.