account_invoice_ubl_peppol: fix tests

Closes #864

account_invoice_ubl_peppol/tests/test_ubl_email_attachment.py

@@ -1,19 +1,18 @@
 # Copyright 2021 Sunflower IT (<https://sunflowerweb.nl>)
 # License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
 
-from odoo.addons.account_tax_unece.tests.test_account_invoice import TestAccountInvoice
+from odoo.addons.account_invoice_ubl.tests.common import TestUblInvoiceCommon
 
 
-class TestAccountInvoiceUblPeppol(TestAccountInvoice):
+class TestAccountInvoiceUblPeppol(TestUblInvoiceCommon):
     def test_ubl_generate_peppol(self):
-        invoice = self.test_only_create_invoice()
+        invoice = self._create_invoice()
         invoice.company_id.xml_format_in_pdf_invoice = "ubl"
         version = "2.1"
-        pdf_file = (
-            self.env.ref("account.account_invoices")
-            .with_context(ubl_version=version, force_report_rendering=True)
-            .render_qweb_pdf(invoice.ids)[0]
-        )
+        report = self.env.ref("account.account_invoices")
+        pdf_file = report.with_context(
+            ubl_version=version, force_report_rendering=True
+        )._render_qweb_pdf(invoice.ids)[0]
         res = self.env["base.ubl"].get_xml_files_from_pdf(pdf_file)
         invoice_filename = invoice.get_ubl_filename(version=version)
         self.assertTrue(invoice_filename in res)