Update javascript/ql/src/experimental/Security/CWE-020/PostMessageNoOriginCheck.qhelp

Co-authored-by: Esben Sparre Andreasen <esbena@github.com>

Author: dellalibera

javascript/ql/src/experimental/Security/CWE-020/PostMessageNoOriginCheck.qhelp

@@ -24,7 +24,7 @@ Always verify the sender's identity of incoming messages.
 <p> In the second example, the `MessageEvent.origin` is verified with an unsecure check. For example, using `event.origin.indexOf('www.example.com') > -1` can be bypassed because the string `www.example.com` could appear anywhere in `event.origin` (i.e. `www.example.com.mydomain.com`)</p>
 <sample src="examples/postMessageWithInsufficientCheck.js" />
 
-<p> In the third example, the `MessageEvent.origin` is properly checked against a trusted origin. 
+<p> In the third example, the `MessageEvent.origin` is properly checked against a trusted origin. </p>
 <sample src="examples/postMessageWithInsufficientCheck.js" />
 
 </example>