remove extra level of context in test that each worker can be applied to at least one image
remove extra level of context in test that each worker can be applied to at least one image

toy/image_optim,mihailim/image_optim,toy/image_optim,ramiroaraujo/image_optim,mihailim/image_optim,weheartit/image_optim,toy/image_optim,weheartit/image_optim,ramiroaraujo/image_optim,ramiroaraujo/image_optim,weheartit/image_optim,mihailim/image_optim