bpo-35800: Deprecate smtpd.MailmanProxy (GH-11675)



Since `smtpd.MailmanProxy` is already broken, it is not formally deprecated in 3.9. It will be removed in 3.10.


https://bugs.python.org/issue35800
diff --git a/Misc/ACKS b/Misc/ACKS
index 71e61c3..d8e2630 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -321,6 +321,7 @@
 Jeffery Collins
 Robert Collins
 Paul Colomiets
+Samuel Colvin
 Christophe Combelles
 Geremy Condra
 Denver Coneybeare