Added statusCode to parent::_contruct

[xtrasmal]

I ran into a case where I got a InvalidArgumentException(code: 0) with the message:
The HTTP status code "0" is not valid while building the response for an exception of the type HttpException.

As you can see, at the moment, the parent is getting the $code variable, which is not set.
The thing that is being used is $statusCode.

This leads to the following:

$exception->getCode results in 0
$exception->getStatusCode results in a http-status code, like 404.

Expected was the following:

$exception->getCode results in 404
$exception->getStatusCode results 404.

This problem only happens when people have a custom exception handler that expects that the inherited getCode method form the extended parent Exception class can be called...which in this case is being set to 0, even though it is a HttpException.

So my proposed solution is to change the constructor
from:

    public function __construct(int $statusCode, string $message = null, \Throwable $previous = null, array $headers = [], ?int $code = 0)
    {
        $this->statusCode = $statusCode;
        $this->headers = $headers;

        parent::__construct($message, $code, $previous);
    }

to:

    public function __construct(int $statusCode, string $message = null, \Throwable $previous = null, array $headers = [], ?int $code = 0)
    {
        $this->statusCode = $statusCode;
        $this->headers = $headers;

        parent::__construct($message, $statusCode, $previous);
    }

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