Bug 20012: use Modern::Perl in Reports perl scripts

Bug 20012: use Modern::Perl in Reports perl scripts

Test Case:
Check the following files have been updated from
use strict;
use warnings;
to
use Modern::Perl;

borrowers_out.pl
cat_issues_top.pl
catalogue_out.pl
catalogue_stats.pl
dictionary.pl
issues_avg_stats.pl
issues_stats.pl
itemslost.pl
manager.pl
reports-home.pl
serials_stats.pl
stats.print.pl

Signed-off-by: Jon Knight <J.P.Knight@lboro.ac.uk>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>