Add aws_key.php
under the root directory manually after clone.
Replace Access key!
<?php
require_once 'vendor/autoload.php';
use Aws\Credentials\Credentials;
use Aws\Exception\AwsException;
$AWS_Credentials = new Aws\Credentials\Credentials(
'Access Key Id', //REPLACE THIS!!!
'Secret access key' //REPLACE THIS!!!
);