Update laravel-vapor NPM / JS script to use XmlHttpRequest

Something like this for example...

let body = new FormData();
body.append('bucket', options.bucket || '');
body.append('content_type', options.contentType || file.type);
body.append('expires', options.expires || '');
body.append('visibility', options.visibility || '');

let payload = {
    method      : 'post',
    credentials : 'same-origin',
    body        : body,
    headers     : {
        'X-Requested-With' : 'XMLHttpRequest',
    },
};

let response = await fetch('/vapor/signed-storage-url', payload);
let data = await response.json();

let headers = data.headers;

if ('Host' in headers) {
    delete headers.Host;
}

data.extension = file.name.split('.').pop();

await function() {
    return new Promise(function (resolve, reject) {

        let xhr = new XMLHttpRequest();
        xhr.open('PUT', data.url);

        xhr.onload = () => resolve(xhr.response);
        xhr.upload.onprogress = (e) => options.progress(Math.ceil((e.loaded / e.total) * 100));

        for (const header in headers) {
            xhr.setRequestHeader(header, headers[header]);
        }

        xhr.send(file);

    });
}();

return data;

I used fetch for the first request since there's no need to monitor upload progress and fetch doesn't require additional logic to work with promises unlike XHR.

You can submit this as a Pull Request so we can review.

Done - https://github.com/laravel/vapor-js/pull/13

:)