Expand tests related to task system
Add test to cancel tasks, to delete a running task, and to delete a nonexistent task.
closes: https://github.com/PulpQE/pulp-smash/issues/976 https://pulp.plan.io/issues/3634 #3634
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Expand tests related to task system
Add test to cancel tasks, to delete a running task, and to delete a nonexistent task.
closes: https://github.com/PulpQE/pulp-smash/issues/976 https://pulp.plan.io/issues/3634 #3634