Bug 28152: Fix import_items row creation if duplicate barcode

Bug 28152: Fix import_items row creation if duplicate barcode

We are trying to insert "duplicate item barcode" into import_items.itemnumber (integer),
it fails with "Incorrect integer value: 'duplicate item barcode' for column 'itemnumber' at row 1"

To reproduce:
Export a biblio with an item
Import it
=> The item is not added, and there is no new row in import_items.

The error only appears in the log if you comment the close STDERR and
close STDOUT lines

Signed-off-by: Joonas Kylmälä <joonas.kylmala@iki.fi>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>