[FIX] account: Set the reference and not the name for Opening Journal Entry.

We have a problem about the opening journal entry because we set the account
move name to "Opening Journal Entry" and it's not compliant with our policy
about the account move name.
We often check the account move name to know if the move has consumed a number.
And we cannot check it correctly for the opening journal entry.

closes odoo/odoo#38957

Signed-off-by: oco-odoo <oco-odoo@users.noreply.github.com>

addons/account/models/company.py

@@ -337,7 +337,7 @@ class ResCompany(models.Model):
                 opening_date = opening_date + relativedelta(years=-1)
 
             self.account_opening_move_id = self.env['account.move'].create({
-                'name': _('Opening Journal Entry'),
+                'ref': _('Opening Journal Entry'),
                 'company_id': self.id,
                 'journal_id': default_journal.id,
                 'date': opening_date,