Oops, missed updating doc to correct version for split

Doc/lib/libstring.tex

@@ -264,7 +264,7 @@ characters are removed.  If given and not \code{None}, \var{chars}
 must be a string; the characters in the string will be stripped from
 the both ends of the string this method is called on.
 \versionchanged[The \var{chars} parameter was added.  The \var{chars}
-parameter cannot be passed in 2.2 or 2.2.1]{2.2.2}
+parameter cannot be passed in earlier 2.2 versions]{2.2.3}
 \end{funcdesc}
 
 \begin{funcdesc}{swapcase}{s}