title: How to set the cookie expire date with `ngx-cookie-service`
body: <p>I am using <code>ngx-cookie-service</code> for my angular5 app. any one help me to show the way to set the expire date?</p>
  
  <p>I try like this:</p>
  
  <pre><code>setCookies($event){
          this.cookieService.set( 'retailAppCookies', "true", 30 );
          this.cookieService.set( 'expires', '2030-07-19' );
      }
  </code></pre>
  
  <p>But not works. any one help me?</p>