Fix a race condition on the bot mode

This caused the history to sometimes be replayed despite the +B mode being set.

breadbot/__main__.py

@@ -7,8 +7,8 @@ from pinhook import plugin, bot
 class BreadBot(bot.Bot):
 
     def on_welcome(self, c, e):
-        super().on_welcome(c, e)
         c.mode(self.bot_nick, '+B')
+        super().on_welcome(c, e)
         for channel in self.chanlist:
             self.process_output(c, channel, plugin.message('bread'))