It will remove the quantity from the cart details.

remove_quantity.php

<?php
/*
* It will remove the selected quantity count from checkout page table.
*/
function remove_quantity_text( $cart_item, $cart_item_key ) {
   $product_quantity= '';
   return $product_quantity;
}

add_filter ('woocommerce_checkout_cart_item_quantity', 'remove_quantity_text', 10, 2 );