[IMP] sale_margin_delivered: Improve UI

Put all the new fields after the orginal margin fields from odoo. (prior to this change, the new fields were displayed among the margin fields from Odoo

sale_margin_delivered/views/sale_margin_delivered_view.xml

@@ -6,7 +6,7 @@
         <field name="model">sale.order</field>
         <field name="inherit_id" ref="sale_margin.sale_margin_sale_order_line_form" />
         <field name="arch" type="xml">
-            <xpath expr="//field[@name='margin']" position="after">
+            <xpath expr="//field[@name='margin_percent']" position="after">
                 <field
                     name="purchase_price_delivery"
                     string="Cost Price dlvd."