During configure journals and to set property stock journal
from stock account , will try to create
xmlid to existing records to avoid duplicate journal codes.
but there are some existing code journal for inventory valuation
already exists. so if already journal with `STJ` and with same
company exist then will avoid to create new journal of same code.
```
psycopg2.errors.UniqueViolation: duplicate key value violates unique constraint "account_journal_code_company_uniq"
DETAIL: Key (company_id, code)=(1, STJ) already exists.
```
closesodoo/odoo#128639
X-original-commit: 6d6a6530bc43f289f8a811347e0ddd7053b5651c
Signed-off-by: William Henrotin (whe) <whe@odoo.com>