Fixed \versionadded for the (?(id/name)yes|no) expression support.

Doc/lib/libre.tex

@@ -304,7 +304,7 @@ is optional and can be omitted. For example,
 \regexp{(<)?(\e w+@\e w+(?:\e .\e w+)+)(?(1)>)} is a poor email matching
 pattern, which will match with \code{'<user@host.com>'} as well as
 \code{'user@host.com'}, but not with \code{'<user@host.com'}.
-\versionadded{2.3}
+\versionadded{2.4}
 
 \end{list}