Bug 15120: runreport.pl cronjob doesn't allow custom subjects anymore

Bug 15120: runreport.pl cronjob doesn't allow custom subjects anymore

To test, well do something like

misc/cronjobs/runreport.pl --subject="My fancy subject!" --to=you@youraddress.com 1
where 1 is the number of your favourite saved report.

Success is your email arrives with the subject "My fancy subject!" Failure is
(with --subject defined) you get either the description of the report, or "Koha
saved report" as the subject. This is success without --subject defined.

Signed-off-by: Frederic Demians <f.demians@tamil.fr>
  Bug repeatable and fixed by this patch.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>