Clear shelf canceled holds notification fix

Clear shelf canceled holds notification fix

After cancelling a batch of holds via the clear-shelf process, before we
send the holds off to action/trigger for potential notification
generation, re-fetch the holds from the DB to pick up the calculated
cancel_time value (i.e. get a real value for "now").  Otherwise, A/T may
die attempting to create a DateTime object by parsing "now".

Signed-off-by: Bill Erickson <berick@esilibrary.com>
Signed-off-by: Mike Rylander <mrylander@gmail.com>