No final account of a fiduciary shall be allowed by any court unless such account shows, and the judge of said court finds, that all income taxes imposed upon said fiduciary, which have become payable, have been paid, and that all taxes which may become due are secured by bond, deposit, or otherwise. The certificate of the commissioner of income tax and the receipt for the amount of the tax therein certified shall be conclusive as to the payment of the tax to the extent of said certificate.