also fix the first code-block

java/ql/src/Security/CWE/CWE-730/ReDoS.qhelp

@@ -11,8 +11,7 @@
 			Consider this regular expression:
 		</p>
 		<sample language="java">
-			^_(__|.)+_$
+^_(__|.)+_$</sample>
-		</sample>
 		<p>
 			Its sub-expression <code>"(__|.)+?"</code> can match the string <code>"__"</code> either by the
 			first alternative <code>"__"</code> to the left of the <code>"|"</code> operator, or by two

javascript/ql/src/Performance/ReDoS.qhelp

@@ -11,8 +11,7 @@
 			Consider this regular expression:
 		</p>
 		<sample language="javascript">
-			/^_(__|.)+_$/
+/^_(__|.)+_$/</sample>
-		</sample>
 		<p>
 			Its sub-expression <code>"(__|.)+?"</code> can match the string <code>"__"</code> either by the
 			first alternative <code>"__"</code> to the left of the <code>"|"</code> operator, or by two

python/ql/src/Security/CWE-730/ReDoS.qhelp

@@ -11,8 +11,7 @@
 			Consider this regular expression:
 		</p>
 		<sample language="python">
-			^_(__|.)+_$
+^_(__|.)+_$</sample>
-		</sample>
 		<p>
 			Its sub-expression <code>"(__|.)+?"</code> can match the string <code>"__"</code> either by the
 			first alternative <code>"__"</code> to the left of the <code>"|"</code> operator, or by two

ruby/ql/src/queries/security/cwe-1333/ReDoS.qhelp

@@ -4,8 +4,7 @@
   <example>
     <p>Consider this regular expression:</p>
     <sample language="ruby">
-      /^_(__|.)+_$/
+/^_(__|.)+_$/</sample>
-    </sample>
     <p>
       Its sub-expression <code>"(__|.)+?"</code> can match the string
       <code>"__"</code> either by the first alternative <code>"__"</code> to the