Fix #116551: gpu.types.Buffer always returning 'FLOAT' type on MacOS

The issue involves using const on a variable that is later modified.

source/blender/python/gpu/gpu_py_buffer.cc

@@ -386,7 +386,7 @@ static PyObject *pygpu_buffer__tp_new(PyTypeObject * /*type*/, PyObject *args, P
     return nullptr;
   }
 
-  const PyC_StringEnum pygpu_dataformat = {bpygpu_dataformat_items, GPU_DATA_FLOAT};
+  PyC_StringEnum pygpu_dataformat = {bpygpu_dataformat_items, GPU_DATA_FLOAT};
   if (!PyArg_ParseTuple(
           args, "O&O|O: Buffer", PyC_ParseStringEnum, &pygpu_dataformat, &length_ob, &init))
   {