feat(web/panettone): Noping issue authors' usernames

When sending irc notifications, insert a zero-width space after the
first character of the username of the author of issues, to prevent that
user from receiving a ping.

Fixes: b/95
Change-Id: Ibcacb45129b2cb99b587744eb61f4f1dbc0060d6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2693
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>

web/panettone/src/irc.lisp

@@ -2,6 +2,12 @@
 
 (in-package :panettone.irc)
 
+(defun noping (s)
+  (format nil "~A~A~A"
+          (char s 0)
+          #\ZERO_WIDTH_SPACE
+          (subseq s 1)))
+
 (defun get-irccat-config ()
   "Reads the IRCCATHOST and IRCCATPORT environment variables, and returns them
 as two values"