[UPDT] view updated 'sale_discount_total

sale_discount_total/views/sale_view.xml

@@ -27,6 +27,8 @@
                             <field name="amount_tax" widget='monetary' options="{'currency_field': 'currency_id'}"/>
                             <div class="oe_subtotal_footer_separator oe_inline o_td_label">
                                 <label for="amount_total" />
+           			<button name="button_dummy"
+                                        states="draft,sent" string="(update)" type="object" class="oe_edit_only oe_link"/>
                             </div>
                             <field name="amount_total" nolabel="1" class="oe_subtotal_footer_separator" widget='monetary' options="{'currency_field': 'currency_id'}"/>
                         </group>