Revoke integration tests are hanging

[kotfic]

Both:

• test_celery.py::test_celery_task_revoke
• test_celery.py::test_celery_task_revoke_in_queue

Are hanging and causing integration tests to fail. (See: #191 maybe?) @cjh1 Would you be willing to take a look (and/or are these features still in use/relevant to any projects?)

[cjh1]

@kotfic I don't really have time to look at this at the moment, has this just started failing?