Add a "What's New" entry for #12170

Doc/whatsnew/3.3.rst

@@ -209,6 +209,13 @@ the equality of the underlying sequences generated by those range objects.
 (:issue:`13021`)
 
 
+The ``count()``, ``find()``, ``rfind()``, ``index()`` and ``rindex()``
+methods of :class:`bytes` and :class:`bytearray` objects now accept an
+integer between 0 and 255 as their first argument.
+
+(:issue:`12170`)
+
+
 New and Improved Modules
 ========================