lable for discount_amount should be configurable (#15408)

diff --git a/erpnext/templates/print_formats/includes/taxes.html b/erpnext/templates/print_formats/includes/taxes.html
index db17c65..377f9a3 100644
--- a/erpnext/templates/print_formats/includes/taxes.html
+++ b/erpnext/templates/print_formats/includes/taxes.html
@@ -2,7 +2,7 @@
 	{%- if doc.discount_amount -%}
 		<div class="row">
 			<div class="col-xs-5 {%- if doc._align_labels_right %} text-right{%- endif -%}">
-				<label>{{ _("Discount Amount") }}</label></div>
+				<label>{{ _(doc.meta.get_label('discount_amount')) }}</label></div>
 			<div class="col-xs-7 text-right">
 				- {{ doc.get_formatted("discount_amount", doc) }}
 			</div>