Skip null EntityTypes

src/main/java/me/libraryaddict/disguise/commands/DisguiseRadiusCommand.java

@@ -39,6 +39,10 @@ public class DisguiseRadiusCommand extends DisguiseBaseCommand implements TabCom
         for (EntityType type : EntityType.values()) {
             Class c = type.getEntityClass();
 
+            if (c == null) {
+                continue;
+            }
+
             while (!validClasses.contains(c)) {
                 validClasses.add(c);