CBQE-0: fix task.py

Change-Id: I12083ca313ae8f4b9a224535eac99aceea3a07c2
Reviewed-on: http://review.couchbase.org/25868
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>