gh-67230: update whatsnew note for csv changes (#103598)

Author: smontanaro

Doc/whatsnew/3.12.rst

@@ -258,7 +258,7 @@ csv
 
 * Add :data:`~csv.QUOTE_NOTNULL` and :data:`~csv.QUOTE_STRINGS` flags to
   provide finer grained control of ``None`` and empty strings by
-  :class:`~csv.reader` and :class:`~csv.writer` objects.
+  :class:`~csv.writer` objects.
 
 inspect
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