update dockertest script
update dockertest script

Signed-off-by: Ying Li <f39392f1e2d21dabc2bc5ab11d2bf832bde87b60@docker.com>

jfrazelle/notary,umayr/notary,johnsandiford/notary,andrewhsu/notary,HuKeping/notary,docker/notary,dqminh/notary,vdemeester/notary,umayr/notary,HuKeping/notary,docker/notary,umayr/notary,dqminh/notary,endophage/notary,vdemeester/notary,andrewhsu/notary,johnsandiford/notary,jfrazelle/notary,andrewhsu/notary,jfrazelle/notary,endophage/notary,vdemeester/notary,dqminh/notary,docker/notary,HuKeping/notary,johnsandiford/notary,endophage/notary