fix: add missing items labels back (#36737)

[skip ci]
diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.json b/erpnext/accounts/doctype/sales_invoice/sales_invoice.json
index 7581366..e5adeae 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.json
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.json
@@ -716,6 +716,7 @@
    "fieldtype": "Table",
    "hide_days": 1,
    "hide_seconds": 1,
+   "label": "Items",
    "oldfieldname": "entries",
    "oldfieldtype": "Table",
    "options": "Sales Invoice Item",