Shipping class dimensions are not determined correctly

[luzat]

In WC_Shipcloud_Shipping::get_shipping_class_dimensions the following line fails to find the requested taxonomy:

$taxonomy = get_term_by( 'name', $shipping_class, 'product_shipping_class' );

The issue is, that $shipping_class is a slug, not the readable name. The line should be changed to:

$taxonomy = get_term_by( 'slug', $shipping_class, 'product_shipping_class' );

Otherwise no shipping class dimensions will be read.