gh-102259: Fix re doc issue regarding right square brackets (#102264)

Co-authored-by: Terry Jan Reedy <[email protected]>

Author: smontanaro

Doc/library/re.rst

@@ -271,7 +271,8 @@ The special characters are:
 
    * To match a literal ``']'`` inside a set, precede it with a backslash, or
      place it at the beginning of the set.  For example, both ``[()[\]{}]`` and
-     ``[]()[{}]`` will both match a parenthesis.
+     ``[]()[{}]`` will match a right bracket, as well as left bracket, braces,
+     and parentheses.
 
    .. .. index:: single: --; in regular expressions
    .. .. index:: single: &&; in regular expressions