[FIX] project: fix can't edit attachment with studio

Issue

    - Install Projects & Studio
    - Go into projects app
    - Edit a project (... => Edit)
    - Click on x attachments stat button

    You can't edit with studio

Cause

    Writing the action manually instead of using the base one
    result with an empty xml_id (and a lot of missing data).

Solution

    Use base.action_attachment like others modules do (e.g. helpdesk).

OPW-2146741

closes odoo/odoo#43263

X-original-commit: 856b09d7055ebbfebbe3b5dc3093e429c8c930ff
Signed-off-by: Jason Van Malder <jvm-odoo@users.noreply.github.com>

addons/project/models/project.py

@@ -96,26 +96,19 @@ class Project(models.Model):
             project.task_count = result.get(project.id, 0)
 
     def attachment_tree_view(self):
-        self.ensure_one()
-        domain = [
+        attachment_action = self.env.ref('base.action_attachment')
+        action = attachment_action.read()[0]
+        action['domain'] = str([
             '|',
-            '&', ('res_model', '=', 'project.project'), ('res_id', 'in', self.ids),
-            '&', ('res_model', '=', 'project.task'), ('res_id', 'in', self.task_ids.ids)]
-        return {
-            'name': _('Attachments'),
-            'domain': domain,
-            'res_model': 'ir.attachment',
-            'type': 'ir.actions.act_window',
-            'view_id': False,
-            'view_mode': 'kanban,tree,form',
-            'help': _('''<p class="o_view_nocontent_smiling_face">
-                        Documents are attached to the tasks of your project.</p><p>
-                        Send messages or log internal notes with attachments to link
-                        documents to your project.
-                    </p>'''),
-            'limit': 80,
-            'context': "{'default_res_model': '%s','default_res_id': %d}" % (self._name, self.id)
-        }
+            '&',
+            ('res_model', '=', 'project.project'),
+            ('res_id', 'in', self.ids),
+            '&',
+            ('res_model', '=', 'project.task'),
+            ('res_id', 'in', self.task_ids.ids)
+        ])
+        action['context'] = "{'default_res_model': '%s','default_res_id': %d}" % (self._name, self.id)
+        return action
 
     @api.model
     def activate_sample_project(self):