Add missing <nickname> parameter to ERR_WASNOSUCHNICK (#235)

All implementations have it

Author: progval

_includes/modern-appendix.md

@@ -833,7 +833,7 @@ Indicates that the `JOIN` command failed because the client has joined their max
 
 {% numericheader ERR_WASNOSUCHNICK %}
 
-      "<client> :There was no such nickname"
+      "<client> <nickname> :There was no such nickname"
 
 Returned as a reply to {% message WHOWAS %} to indicate there is no history information for that nickname.