Hotfix REntityServer

SpigotCore_Main/src/de/steamwar/entity/REntityServer.java

@@ -55,7 +55,7 @@ public class REntityServer implements Listener {
     private static final Function<Object, Integer> getEntityAction;
     static {
         if(Core.getVersion() > 15) {
-            Reflection.MethodInvoker useEntityGetAction = Reflection.getMethod(useEntity, "a");
+            Reflection.MethodInvoker useEntityGetAction = Reflection.getMethod(useEntityEnumAction, "a");
             getEntityAction = value -> ((Enum<?>) useEntityGetAction.invoke(value)).ordinal();
         } else {
             getEntityAction = value -> ((Enum<?>) value).ordinal();