pos/pos_order_remove_line/views/assets.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!--
  ~ Copyright 2019 LevelPrime
  ~ License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl)
  -->
<odoo>
    <template id="assets" inherit_id="point_of_sale.assets">
        <xpath expr="." position="inside">
            <link
                rel="stylesheet"
                type="text/less"
                href="/pos_order_remove_line/static/src/less/order_line.less"
            />
            <script
                type="text/javascript"
                src="/pos_order_remove_line/static/src/js/order_line.js"
            />
        </xpath>
    </template>
</odoo>