[Compose] Update SOGo

docker-compose.yml

@@ -147,7 +147,7 @@ services:
             - phpfpm
 
     sogo-mailcow:
-      image: mailcow/sogo:1.66
+      image: mailcow/sogo:1.68
       environment:
         - DBNAME=${DBNAME}
         - DBUSER=${DBUSER}