Bug Description

WordPress core has a mechanism to disable responsive images through some filters.

add_filter( 'wp_calculate_image_srcset', '__return_empty_array' );
add_filter( 'wp_calculate_image_sizes', '__return_false' );

If we disable responsive images, the Enhance Responsive Image plugin still adds the sizes and srcset values. We should fix this.

Steps to reproduce

1. Add add_filter( 'wp_calculate_image_sizes', '__return_false' ) in your functions.php
2. Add image through Image block
3. See image markup.

Screenshots