Merge pull request #11986 from erik-krogh/redosNote2

RB: add note in ReDoS qhelp that Ruby 3.2 has fixed ReDoS

Author: erik-krogh

ruby/ql/src/queries/security/cwe-1333/ReDoSIntroduction.inc.qhelp

@@ -19,6 +19,12 @@
       shape, increasing the input length by ten characters may make the
       automaton about 1000 times slower.
     </p>
+    <p>
+      Note that Ruby 3.2 and later have implemented a caching mechanism that
+      completely eliminates the worst-case time complexity for the regular
+      expressions flagged by this query. The regular expressions flagged by this
+      query are therefore only problematic for Ruby versions prior to 3.2.
+    </p>
     <p>
       Typically, a regular expression is affected by this problem if it contains
       a repetition of the form <code>r*</code> or <code>r+</code> where the