feat(demo/docs): update docs

Author: tomastrajan

projects/elements-demo/src/app/features/docs/configuration/configuration.component.html

@@ -96,7 +96,7 @@ <h2>Upcoming pre-configuration features</h2>
       Global and granular configuration of <code>isModule</code> flag (script
       type module for ECMAScript modules)
     </li>
-    <li>
+    <li class="done">
       Posibility to use loading and error components (not just
       <code>&#60;ng-template></code>
     </li>