gh-73487: Convert _decimal to use Argument Clinic (part 3) (#137844)

Co-authored-by: Adam Turner <[email protected]>

Author: skirpichev

Include/internal/pycore_global_objects_fini_generated.h

@@ -787,6 +787,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(template)
         STRUCT_FOR_ID(term)
         STRUCT_FOR_ID(text)
+        STRUCT_FOR_ID(third)
         STRUCT_FOR_ID(threading)
         STRUCT_FOR_ID(throw)
         STRUCT_FOR_ID(time)