WooCommerce - remove payment method from emails

gistfile1.txt

<?php // Do not include this if already open!

/**
 * Code goes in theme functions.php.
 */
add_filter( 'woocommerce_get_order_item_totals', 'custom_woocommerce_get_order_item_totals' );

function custom_woocommerce_get_order_item_totals( $totals ) {
  unset( $totals['payment_method'] );
  return $totals;
}

Payment method is listed twice in emails, the above code removes only the one from the table, but there still remains this string: 'Pay with cash upon delivery.' above that table.
Do you, by any chance, know how to remove that string as well?

p.s.: thank you for your gists, Mike!