If, during the pendency of an action, the defendant is summoned as trustee of the plaintiff, the first action may nevertheless proceed so far as to ascertain by a verdict or otherwise, what sum, if any, is due from the defendant; but the court may, on motion of the plaintiff in the trustee action, continue it for judgment until the termination of the trustee action, or until the attachment therein is dissolved by the discharge of the trustee or satisfaction of the judgment otherwise.