title: Rename Related Products title in Woocommerce 3
body: <p>I used to have the following function working to change to Related Products text in Woocommerce.</p>
  
  <pre><code>function my_text_strings( $translated_text, $text, $domain ) {
      switch ( $translated_text ) {
          case 'Related Products' :
              $translated_text = __( 'Related Books', 'woocommerce' );
              break;
      }
      return $translated_text;
  }
  add_filter( 'gettext', 'my_text_strings', 20, 3 );
  </code></pre>
  
  <p>It always worked perfectly, but as of Woocommerce version 3.0 or so, this function no longer works.</p>
  
  <p>How should I fix this in order to make it working in the version 3.0 and up?</p>