Core/Authserver: Partial port of 56cf7ff2a8

Change the "UpdateIfNeed" logic to a deadline_timer

src/server/authserver/Server/AuthSession.cpp

@@ -880,9 +880,6 @@ void AuthSession::RealmListCallback(PreparedQueryResult result)
         } while (result->NextRow());
     }
 
-    // Update realm list if need
-    sRealmList->UpdateIfNeed();
-
     // Circle through realms in the RealmList and construct the return packet (including # of user characters in each realm)
     ByteBuffer pkt;