New footer sidebars

footer-sidebars.txt

    register_sidebar([
        'name'          => __('Footer One', 'sage'),
        'id'            => 'footer-one'
    ] + $config);
    register_sidebar([
        'name'          => __('Footer Two', 'sage'),
        'id'            => 'footer-two'
    ] + $config);
    register_sidebar([
        'name'          => __('Footer Three', 'sage'),
        'id'            => 'footer-three'
    ] + $config);