[REF] test_mass_mailing: update module to new common

PURPOSE

Currently tools and asserts for mail tests are located inside test_mail
module. It makes difficult to re-use them in apps tests or force them to
write custom quick and dirty tools and asserts.

SPECIFICATIONS

Update this module to new tools / asserts / helpers / classes defined in mail
and test_mail.

In this commit we remove the ``MassMailingCase`` and replace it by a fresh
``TestMailCommon`` that is simply updated to hold a marketing user by default.
That way all mocks and asserts are available in all sub test classes.

Coming from common update, we have notably

  * ``BaseFunctionalTest`` class is replaced by the new ``TestMailCommon``
    pimped one;
  * ``assertNotifications`` is replaced by ``assertSinglePostNotifications``
    (shortcut for a simple message_post) or ``assertPostNotifications``
    (complete asserts involving several messages and notifications);
  * correctly invoke ``mock_mail_gateway`` when mocking email sending;
  * replace manual check of sent emails or ``assertEmails`` by
    ``assertSentEmails``;
  * remove custom mocks / checks and replace them by now standard mocks
    and assertions (if any);

LINKS

Task ID 2068986
PR #38070

1 files changed, 2 insertions, 4 deletions

diff --git a/addons/test_mass_mailing/tests/test_mass_mailing.py b/addons/test_mass_mailing/tests/test_mass_mailing.py
index ea6ab8d9ae6..430438e76a0 100644
--- a/addons/test_mass_mailing/tests/test_mass_mailing.py
+++ b/addons/test_mass_mailing/tests/test_mass_mailing.py
@@ -1,16 +1,14 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
-from unittest.mock import patch
 from werkzeug import urls
 
-from odoo.addons.test_mass_mailing.tests.common import MassMailingCase
-from odoo.addons.base.models.ir_config_parameter import IrConfigParameter
+from odoo.addons.test_mass_mailing.tests.common import TestMailCommon
 from odoo.tests.common import TransactionCase, users
 from odoo.tools import mute_logger
 
 
-class TestMassMail(MassMailingCase):
+class TestMassMail(TestMailCommon):
 
     def setUp(self):
         """ In this setup we prepare 20 blacklist entries. We therefore add