Fix missing key

That's been broken for a long time :|

Author: Nincodedo

ninbot-app/src/main/java/dev/nincodedo/ninbot/components/subscribe/SubscribeCommand.java

@@ -48,7 +48,8 @@ public MessageExecutor execute(@NotNull SlashCommandInteractionEvent event,
                 event.getInteraction().getHook().editOriginal(Emojis.CROSS_X).queue();
             }
         } else {
-            messageExecutor.addEphemeralMessage(resourceBundle().getString(""));
+            messageExecutor.addEphemeralMessage(String.format(resourceBundle().getString("command.subscribe"
+                    + ".norolefound"), publicRole.getName()));
         }
         return messageExecutor;
     }