[IMP] mass_mailing: add 'create_date' in subscription list view

This commit will add create_date field in view to display
it as 'Subscription Date' to the user so that concerned people
can know when did the contact subscribed into a mailing list.

Here, now when we will import contacts in mailing.contacts
we are linking the mailing_list in subscription_list_ids
using Command to get the values of create_date.

TaskId-2702607

Part-of: odoo/odoo#82107

addons/mass_mailing/tests/test_mailing_list.py

@@ -243,6 +243,7 @@ class TestMailingContactImport(MassMailCommon):
         # Test that the context key "default_list_ids" is ignored (because we manually set list_ids)
         contact_import.with_context(default_list_ids=(first_list | second_list).ids).action_import()
 
+        self.env['mailing.list'].invalidate_model(['contact_ids'])
         # Check the contact of the first mailing list
         contacts = [
             (contact.name, contact.email)

addons/mass_mailing/views/mailing_contact_views.xml

@@ -150,6 +150,7 @@
                            <field name="opt_out_datetime" readonly="1"/>
                            <field name="opt_out"/>
                            <field name="opt_out_reason_id"/>
+                           <field name="create_date" string="Subscription Date"/>
                         </tree>
                     </field>
                 </sheet>

addons/mass_mailing/views/mailing_subscription_views.xml

@@ -16,6 +16,7 @@
                                 aria-label="Blacklisted" invisible="not is_blacklisted" groups="base.group_user"></i>
                             <field name="contact_id"/>
                         </div>
+                        <field name="create_date" string="Subscription Date"/>
                         <field name="opt_out_datetime" readonly="1"/>
                         <field name="opt_out"/>
                         <field name="opt_out_reason_id"/>
@@ -32,6 +33,7 @@
         <field name="arch" type="xml">
             <tree string="Mailing List Subscriptions">
                 <field name="contact_id"/>
+                <field name="create_date" string="Subscription Date"/>
                 <field name="list_id"/>
                 <field name="opt_out"/>
                 <field name="opt_out_reason_id"/>

addons/mass_mailing/wizard/mailing_contact_import.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
-from odoo import fields, models, tools, _
+from odoo import fields, models, tools, Command, _
 from odoo.tools.misc import clean_context
 
 
@@ -63,7 +63,10 @@ class MailingContactImport(models.TransientModel):
             if email not in existing_contacts:
                 unique_contacts[email] = {
                     'name': name,
-                    'list_ids': self.mailing_list_ids.ids,
+                    'subscription_ids': [
+                        Command.create({'list_id': mailing_list_id.id})
+                        for mailing_list_id in self.mailing_list_ids
+                    ],
                 }
 
         if not unique_contacts: