[FIX] account_edi: fix access to edi documents attachment

Following odoo/odoo@44a4cdb, account.edi.document `attachment_id`
now is restricted, so force getting it's value as superuser.

X-original-commit: b805e90457ef57868b9742b622465ea823b05af2
Part-of: odoo/odoo#111839

addons/account_edi/models/account_edi_document.py

@@ -277,6 +277,10 @@ class AccountEdiDocument(models.Model):
         }
         """
         self.ensure_one()
-        if not self.attachment_id:
+        attachment_sudo = self.sudo().attachment_id
+        if not attachment_sudo:
             return {}
-        return {'attachment_ids': self.attachment_id.ids}
+        if not (attachment_sudo.res_model and attachment_sudo.res_id):
+            # do not return system attachment not linked to a record
+            return {}
+        return {'attachment_ids': attachment_sudo.ids}

addons/account_edi/models/account_move.py

@@ -395,7 +395,7 @@ class AccountMove(models.Model):
         return self.edi_document_ids.filtered(lambda d: d.edi_format_id == edi_format)
 
     def _get_edi_attachment(self, edi_format):
-        return self._get_edi_document(edi_format).attachment_id
+        return self._get_edi_document(edi_format).sudo().attachment_id
 
     ####################################################
     # Import Electronic Document