Bug 21537: Fix typo for options_for_item_types

Bug 21537: Fix typo for options_for_item_types

To test:
 0 - Set UseACQFrameworkForBiblioRecords to 'Use'
 1 - Define a subfield in the ACQ framework linked to authorised value
 'itemtypes'
 2 - Make sure that field is visible
 3 - Create a purchase suggestion
 4 - Accept it
 5 - Go to Acquisitions
 6 - Find a vendor with an open basket, or create one
 7 - Add to the basket using a suggestion
 8 - Choose the suggestion
 9 - Internal server error
10 - Apply patch
11 - Place order form a suggestion again
12 - Confirm that the field linked to itemtypes shows correctly

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>