Bug #48209 Confusing message "Test has succeeded" after test fails due to warnings

There's no need for --verbose for the mysqltest in check-warnings, remove it

mysql-test/mysql-test-run.pl

@@ -3739,7 +3739,6 @@ sub start_check_warnings ($$) {
 
   mtr_add_arg($args, "--skip-safemalloc");
   mtr_add_arg($args, "--test-file=%s", "include/check-warnings.test");
-  mtr_add_arg($args, "--verbose");
 
   if ( $opt_embedded_server )
   {