remove timezone settings, it's not a common case

If you need set timezone, modify the php.ini to change it. Please make this option up to user.

Author: Rivsen

bin/hyperf.php

@@ -5,7 +5,6 @@
 ini_set('display_startup_errors', 'on');
 
 error_reporting(E_ALL);
-date_default_timezone_set('Asia/Shanghai');
 
 ! defined('BASE_PATH') && define('BASE_PATH', dirname(__DIR__, 1));
 ! defined('SWOOLE_HOOK_FLAGS') && define('SWOOLE_HOOK_FLAGS', SWOOLE_HOOK_ALL);