[FIX] l10n_be_intrastat: shipping country

- Create a partner in Germany
- Set an invoice address for this partner in Poland
- Create an invoice for the Poland address, but the delivery to Germany
- Validate invoice

The Intrastat reports the transaction in Poland, while it should be
Germany.

opw-1878590

addons/l10n_be_intrastat/wizard/xml_decl.py

@@ -176,7 +176,7 @@ class XmlDeclaration(models.TransientModel):
             if inv_line.invoice_id.intrastat_country_id:
                 excnt = inv_line.invoice_id.intrastat_country_id.code
             else:
-                excnt = inv_line.invoice_id.partner_id.country_id.code
+                excnt = inv_line.invoice_id.partner_shipping_id.country_id.code or inv_line.invoice_id.partner_id.country_id.code
 
             #Check region
             #If purchase, comes from purchase order, linked to a location,