It gives error because database value is passed in query generated when jobstep > kind == 'batch'. the database value must be ‘’, if jobstep > kind == 'batch' as per check constraint:
"pga_jobstep_check1" CHECK (jstdbname <> ''::name AND jstkind = 's'::bpchar OR jstdbname = ''::name AND (jstkind = 'b'::bpchar OR jstconnstr <> ''
::text))