It prints to MMA's messages notebook because you didn't submit it to the cloud but to the local session. What your code does is that + it deploys returned
TaskObject[..] to the cloud, which does not do anything.
So to find the task you are taking about just take a look at
ScheduledTasks or remove all of them:
RemoveScheduledTask /@ ScheduledTasks
To submit a task to the cloud you'd have to do:
Be careful though because it will be hard to find that task unless you catch the result. It is because cloud tasks are not associated with particular session so you won't find them in
CloudObjets[None, ScheduledTask] which should return such tasks, does not work. :)