Vendor reference number not mapped in object creation

In UI PUT, vendor reference numbers can be mapped via
`"vendorDetail":{"referenceNumbers":[{"refNumberType":"Vendor internal number","refNumber":"000000"}]}}`

But

```
{
"folio_field": "compositePoLines[0].vendorDetail.referenceNumbers[0].refNumber",
"legacy_field": "VendorReferenceNumber",
"value": "",
"description": ""
},
{
"folio_field": "compositePoLines[0].vendorDetail.referenceNumbers[0].refNumberType",
"legacy_field": "VendorReferenceNumber",
"value": "Vendor internal number",
"description": ""
}
```

in config leads to no object being created