Fix typo in output from --sync_include commandline option.

src/sbin/sympa.pl.in

@@ -889,7 +889,7 @@ if ($main::options{'dump'} or $main::options{'dump_users'}) {
         exit 1;
     }
 
-    printf "Members of list %s have been successfully update.\n",
+    printf "Members of list %s have been successfully updated.\n",
         $list->get_id;
     exit 0;
 ## Migration from one version to another