fix: opportunity link is missign from customer (#28110) (#28121)

(cherry picked from commit 4787a75208)

Co-authored-by: Anupam Kumar <anupamvns0099@gmail.com>

erpnext/crm/doctype/opportunity/opportunity.py

@@ -305,6 +305,8 @@ def make_request_for_quotation(source_name, target_doc=None):
 @frappe.whitelist()
 def make_customer(source_name, target_doc=None):
 	def set_missing_values(source, target):
+		target.opportunity_name = source.name
+
 		if source.opportunity_from == "Lead":
 			target.lead_name = source.party_name