Bug 29321: Remove a last without loop context

Bug 29321: Remove a last without loop context

This reads better when converted to regular if.
Note that last within such a block is allowed in Perl, but it feels
better to use it only in a loop context.

Test plan:
Read the patch ;)
Bonus: Test if you enter the block by using pref OPACSuggestionMandatoryFields
when adding a suggestion from opac.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Edit: Added a space between 'if' and '(' :-D

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>