PyObject_GC_Resize doesn't check preheader size

The PyObject_GC_Resize implementation in the main branch doesn't check if the object has a preheader:

Lines 2357 to 2358 in 0ef92d9

     PyGC_Head *g = AS_GC(op);  
   g = (PyGC_Head *)PyObject_Realloc(g, sizeof(PyGC_Head) + basicsize);  
 

The only internal use I see is by _PyTuple_Resize which doesn't have a preheader, but the PyObject_GC_Resize function is publicly documented.

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	PyGC_Head *g = AS_GC(op);
	g = (PyGC_Head *)PyObject_Realloc(g, sizeof(PyGC_Head) + basicsize);