contact messages: drop the accent focus outline on the trigger

frontend/src/assets/pagerite.css

@@ -936,11 +936,6 @@ article {
   text-shadow: 0 0 0.1em;
 }
 
-.contact-trigger:focus-visible {
-  outline: 2px solid var(--accent);
-  outline-offset: 2px;
-}
-
 /* Unread (a new admin reply, or unanswered threads on the corner icon —
    the .has-unread class, set by contact-main): a scale-up with a shake
    every few seconds to draw the eye, stopping when read (the class goes