fix: add BanEntry to __all__ exports in guild.py

Author: Lumabots

discord/guild.py

@@ -88,7 +88,7 @@
 from .welcome_screen import WelcomeScreen, WelcomeScreenChannel
 from .widget import Widget
 
-__all__ = ("Guild",)
+__all__ = ("Guild", "BanEntry")
 
 MISSING = utils.MISSING