Ensure that materials ready for loan display the correct "Lån før XX-…

…XX-XXXX" date.

I am not a big fan of the `fetchDigitalMaterial` and `fetchMaterial` higher-order components. They are too difficult to read. Maybe these should be rewritten in the future. However, from what I can see, there is never an `identifier` in the props. Therefore, the `isDigital` variable is never set to true. This causes `getInfo` inside `src/apps/reservation-list/reservation-material/reservation-info.tsx` to use `pickupDeadline` instead of `expiryDate`, which is the intended behavior for digital materials.

src/apps/reservation-list/reservation-material/reservation-material.tsx

@@ -12,7 +12,6 @@ export interface ReservationMaterialProps {
   reservation: ReservationType;
   focused: boolean;
   openReservationDetailsModal: (reservation: ReservationType) => void;
-  identifier?: string | null;
   dataCy?: string;
 }
 
@@ -21,13 +20,12 @@ const ReservationMaterial: FC<ReservationMaterialProps & MaterialProps> = ({
   reservation,
   focused,
   openReservationDetailsModal,
-  identifier,
   dataCy = "reservation-material"
 }) => {
   const openDetailsModal = () => {
     openReservationDetailsModal(reservation);
   };
-  const isDigital = !!identifier;
+  const isDigital = !!material?.externalProductId;
 
   return (
     <li>