Bug 8918: (follow-up) allow t/db_dependent/Reserves.t to pass if marcflavour is UNIMARC

Bug 8918: (follow-up) allow t/db_dependent/Reserves.t to pass if marcflavour is UNIMARC

Set marcflavour to MARC21 to make tests pass.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Works for MARC21. But I would prefer a better fix for UNIMARC.
Will send a follow-up for that.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit adc09764bc90c34300444c5ea43bfd040f0d571d)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>