fixed tests for PHP 7.2
fixed tests for PHP 7.2

twigphp/Twig,twigphp/Twig,twigphp/Twig,nicolas-grekas/Twig,gencer/Twig,nicolas-grekas/Twig,gencer/Twig,nicolas-grekas/Twig,nicolas-grekas/Twig,nicolas-grekas/Twig