Update CONTRIBUTORS for BLAKE2 PR

Author: peterdettman

CONTRIBUTORS.html

@@ -568,6 +568,7 @@
 <li>Linuka Ratnayake &lt;https://github.com/linukaratnayake&gt; - initial patches for including KEM-type algorithms in TLS key shares.</li>
 <li>Rune Flobakk &lt;https://github.com/runeflobakk&gt; - initial gradle mods for BOM (Bill of Materials) creation.</li>
 <li>Jon Marius Venstad &lt;https://github.com/jonmv&gt; - Fixed a KangarooTwelve padding bug caused by premature absorption of queued data.</li>
+<li>Lomig Mégard &lt;https://github.com/lomigmegard&gt; - BLAKE2 defensive improvements and cleanup.</li>
 </ul>
 </body>
 </html>