[FIX] hr_expense_invoice: Proper partner

If an expense report includes invoices from different providers,
when posting move the report moves to "paid" and invoices are not
reconciled as paid, as it fails to reconcile the lines with the
transfer moves.

Use the correct partner, from current expense line from the report,
not always the same partner from first expense line.

Fixes #273

hr_expense_invoice/models/hr_expense_sheet.py

@@ -36,8 +36,8 @@ def _do_create_moves(self):
                     lambda x: x.display_type == "payment_term"
                 )
                 transfer_line = move.line_ids.filtered(
-                    lambda x: x.partner_id
-                    == self.expense_line_ids.invoice_id.partner_id
+                    lambda x, partner=expense.invoice_id.partner_id:
+                         x.partner_id == partner
                 )
                 (ap_lines + transfer_line).reconcile()
         return res