Declare experimental free-threaded Python support

Summary: Add experimental support for free-threaded Python.

Reviewed By: grantlouisherman

Differential Revision: D99869989

fbshipit-source-id: 1d99132841a7758c2f808a0a6176412c46dcffe1

Author: yoney

cinderx/_cinderx-lib.cpp

@@ -1585,6 +1585,9 @@ PyModuleDef_Slot _cinderx_slots[] = {
     {Py_mod_exec, reinterpret_cast<void*>(_cinderx_exec)},
 #if PY_VERSION_HEX >= 0x030C0000
     {Py_mod_multiple_interpreters, Py_MOD_MULTIPLE_INTERPRETERS_NOT_SUPPORTED},
+#endif
+#if PY_VERSION_HEX >= 0x030E0000
+    {Py_mod_gil, Py_MOD_GIL_NOT_USED},
 #endif
     {0, nullptr}};