[13.0][IMP] base_ubl: hook to add the AdditionalAccountID ubl field

Added a _ubl_get_additional_reference method to be able to add the AdditionalAccountID ubl field in the _ubl_add_supplier_party

base_ubl/models/ubl.py

@@ -200,6 +200,9 @@ def _ubl_add_party(
     def _ubl_get_customer_assigned_id(self, partner):
         return partner.commercial_partner_id.ref
 
+    def _ubl_get_additional_reference(self, partner):
+        return ""
+
     @api.model
     def _ubl_add_customer_party(
         self, partner, company, node_name, parent_node, ns, version="2.1"
@@ -219,6 +222,12 @@ def _ubl_add_customer_party(
                 customer_party_root, ns["cbc"] + "SupplierAssignedAccountID"
             )
             customer_ref.text = partner_ref
+        additional_ref = self._ubl_get_additional_reference(partner)
+        if additional_ref:
+            additional_ref_node = etree.SubElement(
+                customer_party_root, ns["cbc"] + "AdditionalAccountID"
+            )
+            additional_ref_node.text = additional_ref
         self._ubl_add_party(
             partner, company, "Party", customer_party_root, ns, version=version
         )