Update variant description based on attribute if not already there (#11302)

diff --git a/erpnext/controllers/item_variant.py b/erpnext/controllers/item_variant.py
index 8ca4f70..f40d519 100644
--- a/erpnext/controllers/item_variant.py
+++ b/erpnext/controllers/item_variant.py
@@ -201,14 +201,16 @@
 	variant.variant_of = item.name
 	variant.has_variants = 0
 	if not variant.description:
-		variant.description = ''
+		variant.description = ""
 
 	if item.variant_based_on=='Item Attribute':
 		if variant.attributes:
-			if not variant.description:
-				variant.description += "\n"
-				for d in variant.attributes:
-					variant.description += "<div>" + d.attribute + ": " + cstr(d.attribute_value) + "</div>"
+			attributes_description = ""
+			for d in variant.attributes:
+				attributes_description += "<div>" + d.attribute + ": " + cstr(d.attribute_value) + "</div>"
+			
+			if attributes_description not in variant.description:
+					variant.description += attributes_description
 
 def make_variant_item_code(template_item_code, template_item_name, variant):
 	"""Uses template's item code and abbreviations to make variant's item code"""