Fix typo in _swappedbytes_ in ctypes comment (python#102773)

It's a minor typo, but it makes for a misleading comment.  Let's fix it.

Author: matthiasgoergens

Lib/ctypes/_endian.py

@@ -37,7 +37,7 @@ class _swapped_union_meta(_swapped_meta, type(Union)): pass
 ################################################################
 
 # Note: The Structure metaclass checks for the *presence* (not the
-# value!) of a _swapped_bytes_ attribute to determine the bit order in
+# value!) of a _swappedbytes_ attribute to determine the bit order in
 # structures containing bit fields.
 
 if sys.byteorder == "little":