Bug 24553: Use 'barcode' not 'item_id' when removing hold from SIP patron

Bug 24553: Use 'barcode' not 'item_id' when removing hold from SIP patron

The drop_hold routine was using the wrong parameter for item info in the patron's
array of holds. We store it as 'barcode' not 'item_id'. This is true for both waiting and unavailable
holds

To test:
1 - Apply unit tests patch
2 - prove -v t/db_dependent/SIP/ILS.t
3 - It fails
4 - Apply second patch
5 - prove -v t/db_dependent/SIP/ILS.t
6 - It passes!

You can also see bug 24175 - you cna hack sip_cli_emulator to allow cancelling a hold
and check the messages, test coverage is improved by this patch and should be sufficient
for testing

Signed-off-by: Andrew Fuerste-Henry <andrew@bywatersolutions.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>