Bug 33270: (QA follow-up) Do not change param hashref

Bug 33270: (QA follow-up) Do not change param hashref

Might just be a theoretical thing now, but safer to clone.

Test plan:
Run t/db_dependent/Koha/Biblio/Metadata.t

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit cfbe8daf2118f0ecdeea13ef866e86d2e905b686)
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 32db2823b89ae7250dbd35d5931f682e9a6ce4e2)
Signed-off-by: Matt Blenkinsop <matt.blenkinsop@ptfs-europe.com>