UPGRADE: Update mailing list archive link

Change-Id: I176fe0eaa56c15b34119aa3ace9c37a1ff73a974

Author: supertassu

UPGRADE

@@ -3,7 +3,8 @@ specific problems, you should check:
 
 * the docs at https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Contents ;
 * the mediawiki-l mailing list archive at
-  https://lists.wikimedia.org/pipermail/mediawiki-l/ ; and
+  https://lists.wikimedia.org/hyperkitty/list/mediawiki-l@lists.wikimedia.org/ ;
+  and
 * the bug tracker at https://phabricator.wikimedia.org/
 
 … for information and workarounds to common issues.