[core] Stop waiting for dependencies when cancelling tasks

[dayshah]

Why are these changes needed?

ray.cancel will not appropriately mark the outputs of it's task as cancelled if there are objects that the task depends on that are not yet completed.

1. Inside NormalTaskSubmitter::CancelTask, before we'd have a no-op for tasks with unfinished dependencies. It would just add to the cancelled_tasks list which would be checked when the tasks's dependencies are resolved and then call FailOrRetry then. So now we're failing the task during the actual cancel, cancelling the worker lease if possible, and cancelling the dependency resolution in the dependency resolver so it is no longer in the resolver's pending_tasks. Lines 729-732
2. Now that we're failing there we have to remove the FailOrRetry that exists when the dependencies have been resolved and the task was cancelled or else we'll end up with failing twice. old FailOrRetry
3. The last issue was that with this new logic tasks that have been marked finished could end up inside the TaskManager::FailPendingTask which has a RAY_CHECK to make sure the status isn't Finished or Failed. Now we check before cancelling whether the task has been finished or cancelled.

Related issue number

Closes #46315

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