fix tag to tags

docs/modules/tutorials/pages/beginner/hello_input_system.adoc

@@ -370,7 +370,7 @@ inputManager.addMapping("Pause",  new KeyTrigger(usersPauseKey));
 TIP: Use xref:ROOT:jme3/faq.adoc#how-do-i-switch-between-third-person-and-first-person-view[flyCam.setEnabled(false);]
 
 
-include::partial$proposed-solutions-important.adoc[tag=solution;input]
+include::partial$proposed-solutions-important.adoc[tags=solution;input]
 
 
 == Conclusion