Change New Google Recaptcha (v2) Width

Here is a work around but not always a great one, depending on how much you scale it. Explanation can be found here: https://www.geekgoddess.com/how-to-resize-the-google-nocaptcha-recaptcha/

.g-recaptcha {
    transform:scale(0.77);
    transform-origin:0 0;
}

UPDATE:
Google has added support for a smaller size via a parameter. Have a look at the docs – https://developers.google.com/recaptcha/docs/display#render_param