Call manually CDN Font Awesome for AMP Page

/* Call manually CDN Font Awesome for AMP Page */
function add_fontawesome_cdn() {
    // echo '<link href="https://cdn.jsdelivr.net/npm/@fortawesome/fontawesome-free@5.15.3/css/fontawesome.min.css" rel="stylesheet" type="text/css">';
    echo '<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.3/css/all.min.css" integrity="sha512-iBBXm8fW90+nuLcSKlbmrPcLa0OT92xO1BIsZ+ywDWZCvqsWgccV3gFoRBv0z+8dLJgyAHIhR35VZc2oM/gI1w==" crossorigin="anonymous" referrerpolicy="no-referrer" />';
}
add_action( 'amp_post_template_head', 'add_fontawesome_cdn' );