Ignore all bots when checking if the bot is alone

src/main/java/com/jagrosh/jmusicbot/audio/AloneInVoiceHandler.java

@@ -93,6 +93,6 @@ public class AloneInVoiceHandler
         return guild.getAudioManager().getConnectedChannel().getMembers().stream()
                 .noneMatch(x ->
                         !x.getVoiceState().isDeafened()
-                        && x.getIdLong() != bot.getJDA().getSelfUser().getIdLong());
+                        && !x.getUser().isBot());
     }
 }