fix indent #36

Author: onukura

index.html

@@ -178,7 +178,7 @@ <h2>
             <a class="post-link" href="https://github.com/onukura/gitbucket-swagger-plugin"><span class="fa fa-ellipsis-h"></span>Swagger plugin</a>
         </h2>
         <p>A plugin for rendering a Swagger (OpenAPI) files.</p>
-    </li>
+      </li>
 </ul>
     <p class="separator"/>
     <p>Your plugin is not listed here? You want to move your plugin under the organization? Please open a <a href="https://github.com/gitbucket-plugins/gitbucket-plugins.github.io/issues">ticket/issue</a> to reference your demand.</p>