Bug 18137: Make /holds Mojolicious::Plugin::OpenAPI compatible

Bug 18137: Make /holds Mojolicious::Plugin::OpenAPI compatible

Also
- adding some missing and new response definitions into Swagger spec.
- fixing failing tests due to Bug 17932's change of boolean values

To test:
1. prove t/db_dependent/api/v1/holds.t

Signed-off-by: Olli-Antti Kivilahti <olli-antti.kivilahti@jns.fi>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>