Fix thank typo in coe

Author: krivard

themes/delphi/layouts/_default/coe.html

@@ -38,7 +38,7 @@ <h2>Supporters</h2>
         </ul>
       </div>
       <div class="about-collaborator-special">
-        <h3>Special thank to</h3>
+        <h3>Special thanks to</h3>
         <ul>
           <li>U.S. Centers for Disease Control and Prevention (US CDC)</li>
         </ul>