Bug 35148: before_send_messages plugin hook does not pass the --where option

Bug 35148: before_send_messages plugin hook does not pass the --where option

The before_send_messages plugin hook currently sends all the non-smtp related options with the exception of the --where option. This should be added.

Test Plan:
1) Install the latest version of the kitchen sink plugin (
   https://github.com/bywatersolutions/dev-koha-plugin-kitchen-sink/releases
   )
2) Apply this patch
3) Run process_message_queue.pl with a --where option
4) Run the command: ./misc/cronjobs/process_message_queue.pl --where "letter_code='test'"
5) Note the output looks like:
Plugin hook before_send_message called with the params: $VAR1 = {
          'verbose' => 0,
          'where' => 'letter_code=\'test\'',
          'letter_code' => [],
          'type' => [],
          'limit' => undef
        };

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>