Bug 20013: use Modern::Perl in Reserve perl script

Test plan:
Check the following files that use strict; use warnings; doesn't exist
and use Modern::Perl; is written instead.
modrequest.pl
modrequest_suspendall.pl
placerequest.pl

Signed-off-by: Owen Leonard <oleonard@myacpl.org>

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>

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

reserve/modrequest.pl

@@ -22,8 +22,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Koha; if not, see <http://www.gnu.org/licenses>.
 
-use strict;
-use warnings;
+use Modern::Perl;
 use CGI qw ( -utf8 );
 use C4::Output;
 use C4::Reserves;

reserve/modrequest_suspendall.pl

@@ -22,8 +22,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Koha; if not, see <http://www.gnu.org/licenses>.
 
-use strict;
-use warnings;
+use Modern::Perl;
 use CGI qw ( -utf8 );
 use C4::Output;
 use C4::Reserves;

reserve/placerequest.pl

@@ -21,8 +21,7 @@
 # You should have received a copy of the GNU General Public License
 # along with Koha; if not, see <http://www.gnu.org/licenses>.
 
-use strict;
-use warnings;
+use Modern::Perl;
 
 use CGI qw ( -utf8 );
 use C4::Biblio;