admin stealth mode now works while deadminned (#6630)

this is admittedly not a usual use of stealth mode but it's nice to not
pop on/off the list when deadminned

(this is nice for event rounds since you're supposed to deadmin if in a
conflict role)

code/modules/admin/admin.dm

@@ -653,7 +653,7 @@ var/global/floorIsLava = 0
 		if(!check_rights(R_SERVER,0))
 			message = sanitize(message, 500, extra = 0)
 		message = replacetext(message, "\n", "<br>") // required since we're putting it in a <p> tag
-		to_chat(world, "<span class=notice><b>[usr.client.holder.fakekey ? "Administrator" : usr.key] Announces:</b><p style='text-indent: 50px'>[message]</p></span>")
+		to_chat(world, "<span class=notice><b>[usr.client.is_under_stealthmin() ? "Administrator" : usr.key] Announces:</b><p style='text-indent: 50px'>[message]</p></span>")
 		log_admin("Announce: [key_name(usr)] : [message]")
 	feedback_add_details("admin_verb","A") //If you are copy-pasting this, ensure the 2nd parameter is unique to the new proc!