Remove stray </p> tag

Author: Felicity Chapman

cpp/ql/src/Critical/OverflowCalculated.qhelp

@@ -12,7 +12,6 @@ This query finds calls to:</p>
 zero terminator into consideration.</li>
 <li><code>strcat</code> or <code>strncat</code> that use buffers that are too small to contain the new string.</li>
 </ul>
-</p>
 
 <p>
 The highlighted expression will cause a buffer overflow because the buffer is too small to contain