odoo16/addons/mrp_subcontracting/views/supplier_info_views.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <record id="product_supplierinfo_subcontractor_tree_view" model="ir.ui.view">
        <field name="name">product.supplierinfo.subcontractor.tree.view</field>
        <field name="model">product.supplierinfo</field>
        <field name="inherit_id" ref="product.product_supplierinfo_tree_view"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='partner_id']" position="after">
                <field name="is_subcontractor" readonly="1" optional="hide"/>
            </xpath>
        </field>
    </record>
</odoo>