title: Custom meta data added to Woocommerce not displayed in order item meta
body: <p>I've a single piece of custom metadata to a WooCommerce order and now I want to display this on the thank you page after checkout, however, the data isn't available. The data is saved and available in the admin, I just can't seem to access it.</p>
  
  <pre><code>function custom_order_item_meta( $item_id, $values ) {
  
      if ( ! empty( $values['custom_option'] ) ) {
          woocommerce_add_order_item_meta( $item_id, 'custom_option', $values['custom_option'] );           
      }
  }
  add_action( 'woocommerce_add_order_item_meta', 'custom_order_item_meta', 10, 2 );
  </code></pre>
  
  <p>But when I dump out the <code>wc_get_order</code> my meta data isn't there. </p>
  
  <p>I'm using;</p>
  
  <p><code>woocommerce_add_order_item_meta()</code> 
  to save the data but dumping out <code>var_dump(wc_get_order( $order-&gt;id ));</code> also doesn't show my custom meta field</p>
  
  <p>is there another hook I should be using to access this data?</p>