Bug 26460: Fix line ending in JSON

Bug 26460: Fix line ending in JSON

Wrong line ending in JSON causes error:
Uncaught SyntaxError: missing } after property list
note: { opened at line 29579, column 15

To test:
1 - Have a title with some items not for hold in staff interface
2 - Set AllowHoldPolicyOverride to 'Allow'
3 - Attempt to place hold on the title
4 - Note JS error in the console and datatable does not load for items
5 - Apply patch
6 - Reload
7 - Error is cleared, table loads correctly

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>