Bug 10407: [QA Follow-up] Hashref process_batch params

Bug 10407: [QA Follow-up] Hashref process_batch params

As requested by Mark Tompsett. Hope this guarantees a signoff now..

Note: For consistency four additional parameters were needed to no longer
use file level vars in this subroutine.

Test plan:
Import a file with stage_file.pl.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Imported a marc file and a marcxml file with stage_file.pl.

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