Bug 12446: Limit available categories when using "Add guarantee" button

Bug 12446: Limit available categories when using "Add guarantee" button

Test plan:
1) Have some patron categories that can and cannot be guarantee
2) Visit a patron's account and click the "Add guarantee" button
3) In the "category" dropdown, note that all categories are available
4) Apply this patch
5) Repeat step 2 and 3; the dropdown now only contains the categories
for which "can be guarantee" is set to "Yes".

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>