Bug 34930: Change timezone in Koha/Object.t where tests assume it

Bug 34930: Change timezone in Koha/Object.t where tests assume it

This is the case for subtest: attributes_from_api() tests.

Test plan:
export TZ='Europe/Amsterdam'
prove t/db_dependent/Koha/Object.t

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 0fb84e424e005179480faddb5d7d646bb594ea7b)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>