fix: hsn-wise summary is incorrect if an invoice has repeated item code
diff --git a/erpnext/regional/report/hsn_wise_summary_of_outward_supplies/hsn_wise_summary_of_outward_supplies.py b/erpnext/regional/report/hsn_wise_summary_of_outward_supplies/hsn_wise_summary_of_outward_supplies.py
index e03ad37..1c1335e 100644
--- a/erpnext/regional/report/hsn_wise_summary_of_outward_supplies/hsn_wise_summary_of_outward_supplies.py
+++ b/erpnext/regional/report/hsn_wise_summary_of_outward_supplies/hsn_wise_summary_of_outward_supplies.py
@@ -114,9 +114,11 @@
 
 	items = frappe.db.sql("""
 		select
-			`tabSales Invoice Item`.name, `tabSales Invoice Item`.base_price_list_rate,
-			`tabSales Invoice Item`.gst_hsn_code, `tabSales Invoice Item`.stock_qty,
-			`tabSales Invoice Item`.stock_uom, `tabSales Invoice Item`.base_net_amount,
+			`tabSales Invoice Item`.gst_hsn_code,
+			`tabSales Invoice Item`.stock_uom,
+			sum(`tabSales Invoice Item`.stock_qty) as stock_qty,
+			sum(`tabSales Invoice Item`.base_net_amount) as base_net_amount,
+			sum(`tabSales Invoice Item`.base_price_list_rate) as base_price_list_rate,
 			`tabSales Invoice Item`.parent, `tabSales Invoice Item`.item_code,
 			`tabGST HSN Code`.description
 		from `tabSales Invoice`, `tabSales Invoice Item`, `tabGST HSN Code`
@@ -124,6 +126,8 @@
 			and `tabSales Invoice`.docstatus = 1
 			and `tabSales Invoice Item`.gst_hsn_code is not NULL
 			and `tabSales Invoice Item`.gst_hsn_code = `tabGST HSN Code`.name %s %s
+		group by
+			`tabSales Invoice Item`.parent, `tabSales Invoice Item`.item_code
 
 		""" % (conditions, match_conditions), filters, as_dict=1)