Bug 28959: Fix occurrence in tools/batch_record_modification.pl

Bug 28959: Fix occurrence in tools/batch_record_modification.pl

No method count found for Koha::Virtualshelves DBIx::Class::Storage::DBI::_dbh_execute(): DBI Exception: DBD::mysql::st execute failed: Unknown column 'category' in 'where clause' at /kohadevbox/koha/Koha/Objects.pm line 601                                                                                                                                                                             at /kohadevbox/koha/koha-tmpl/intranet-tmpl/prog/en/modules/tools/batch_record_modification.tt line 80.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>