title: Responsive property does not work on react-slick
body: <p>I want to change <code>sliderToShow</code> property on small devices but the <code>responsive</code> property does not work.</p>
  
  <pre><code>let settings_3 = {
    dots: false,
    autoplay: false,
    autoplaySpeed: 3000,
    slidesToShow: 3,
  
    responsive: [{
      breakpoint: 600,
      settings_3: {
        slidesToShow: 2,
        slidesToScroll: 2,
        initialSlide: 2
      }
    }]
  };
  </code></pre>