do not copy template description to variant if not in allow fields (#13726)

diff --git a/erpnext/controllers/item_variant.py b/erpnext/controllers/item_variant.py
index 7749ac5..a544119 100644
--- a/erpnext/controllers/item_variant.py
+++ b/erpnext/controllers/item_variant.py
@@ -272,18 +272,19 @@
 				else:
 					variant.set(field.fieldname, item.get(field.fieldname))
 
-	variant.variant_of = item.name
-	variant.has_variants = 0
-	if not variant.description:
-		variant.description = ""
+	if 'description' in allow_fields:
+		variant.variant_of = item.name
+		variant.has_variants = 0
+		if not variant.description:
+			variant.description = ""
 
-	if item.variant_based_on=='Item Attribute':
-		if variant.attributes:
-			attributes_description = ""
-			for d in variant.attributes:
-				attributes_description += "<div>" + d.attribute + ": " + cstr(d.attribute_value) + "</div>"
+		if item.variant_based_on=='Item Attribute':
+			if variant.attributes:
+				attributes_description = ""
+				for d in variant.attributes:
+					attributes_description += "<div>" + d.attribute + ": " + cstr(d.attribute_value) + "</div>"
 
-			if attributes_description not in variant.description:
+				if attributes_description not in variant.description:
 					variant.description += attributes_description
 
 def make_variant_item_code(template_item_code, template_item_name, variant):