dispatcher: add tests for different combinations of resource references and direct secrets and configs in tasks
dispatcher: add tests for different combinations of resource references and direct secrets and configs in tasks

Signed-off-by: Riyaz Faizullabhoy <97794a5efeea78234636d4fba0f499c15a92f5e3@docker.com>

AliyunContainerService/swarmkit,docker/swarmkit,dperny/swarmkit-1,alyyousuf7/swarmkit,AliyunContainerService/swarmkit,cheyang/swarmkit,dperny/swarmkit-1,alyyousuf7/swarmkit,cheyang/swarmkit,jlhawn/swarmkit,sungwonh/swarmkit,jlhawn/swarmkit,sungwonh/swarmkit,docker/swarmkit