fix w3 validation check

Author: Thierry Boileau

content/documentation/javadocs/2.5/gwt.md

@@ -13,6 +13,7 @@ weight: 2
       <ul>
         <li><a href="https://javadoc.io/doc/org.restlet.gwt/org.restlet.gwt.ext.json/{{% param version %}}/">JSON extension</a></li>
         <li><a href="https://javadoc.io/doc/org.restlet.gwt/org.restlet.gwt.ext.xml/{{% param version %}}/">XML extension</a></li>
+      </ul>
     </li>
   </ul>
 </div>

content/documentation/javadocs/2.5/java.md

@@ -35,6 +35,7 @@ weight: 1
         <li><a href="https://javadoc.io/doc/org.restlet/org.restlet.ext.thymeleaf/{{% param version %}}/">Thymeleaf extension</a></li>
         <li><a href="https://javadoc.io/doc/org.restlet/org.restlet.ext.velocity/{{% param version %}}/">Velocity extension</a></li>
         <li><a href="https://javadoc.io/doc/org.restlet/org.restlet.ext.xml/{{% param version %}}/">XML extension</a></li>
+      </ul>
     </li>
   </ul>
 </div>

content/documentation/javadocs/2.6/gwt.md

@@ -13,6 +13,7 @@ weight: 2
       <ul>
         <li><a href="https://javadoc.io/doc/org.restlet.gwt/org.restlet.gwt.ext.json/{{% param version %}}/">JSON extension</a></li>
         <li><a href="https://javadoc.io/doc/org.restlet.gwt/org.restlet.gwt.ext.xml/{{% param version %}}/">XML extension</a></li>
+      </ul>
     </li>
   </ul>
 </div>

content/documentation/javadocs/2.6/java.md

@@ -29,6 +29,7 @@ weight: 1
         <li><a href="https://javadoc.io/doc/org.restlet/org.restlet.ext.thymeleaf/{{% param version %}}/">Thymeleaf extension</a></li>
         <li><a href="https://javadoc.io/doc/org.restlet/org.restlet.ext.velocity/{{% param version %}}/">Velocity extension</a></li>
         <li><a href="https://javadoc.io/doc/org.restlet/org.restlet.ext.xml/{{% param version %}}/">XML extension</a></li>
+      </ul>
     </li>
   </ul>
 </div>