Exclude _Ci_PySetTStateForGC from the limited API

Summary:
Looks like we need one more fix to get the generated files check happy - we need to make sure _Ci_PySetTStateForGC doesn't show up in the limited API.

https://github.com/facebookincubator/cinder/actions/runs/27295349367/job/80626496749

Reviewed By: itamaro

Differential Revision: D108175515

fbshipit-source-id: 976df317234fd31f86c26b98e58966b2d619723d

Author: DinoV

Include/pystate.h

@@ -119,8 +119,10 @@ PyAPI_FUNC(void) PyGILState_Release(PyGILState_STATE);
 */
 PyAPI_FUNC(PyThreadState *) PyGILState_GetThisThreadState(void);
 
+#ifndef Py_LIMITED_API
 // Sets the thread state for multi-threaded GC
 PyAPI_FUNC(void) _Ci_PySetTStateForGC(PyThreadState *tstate);
+#endif
 
 #ifndef Py_LIMITED_API
 #  define Py_CPYTHON_PYSTATE_H