kraken: fix for the first day of production
kraken: fix for the first day of production

with parameter datetime_represents=arrival, no need to search for the
previous day if today is the first production date of data.

kadhikari/navitia,pbougue/navitia,Tisseo/navitia,patochectp/navitia,kinnou02/navitia,xlqian/navitia,xlqian/navitia,Tisseo/navitia,patochectp/navitia,kinnou02/navitia,Tisseo/navitia,kadhikari/navitia,pbougue/navitia,CanalTP/navitia,pbougue/navitia,Tisseo/navitia,CanalTP/navitia,kadhikari/navitia,pbougue/navitia,antoine-de/navitia,kinnou02/navitia,kadhikari/navitia,kinnou02/navitia,patochectp/navitia,xlqian/navitia,Tisseo/navitia,xlqian/navitia,antoine-de/navitia,CanalTP/navitia,antoine-de/navitia,xlqian/navitia,patochectp/navitia,CanalTP/navitia,antoine-de/navitia,CanalTP/navitia