[Spot] Correct hint after ctrl-c from `sky spot launch` during streaming logs

[Michaelvll]

Currently, when we ctrl-c from sky spot launch the hint for canceling jobs should be sky spot cancel, but the current output is as following:

I 10-04 15:56:40 cloud_vm_ray_backend.py:2080] Job ID: 17
I 10-04 15:56:40 cloud_vm_ray_backend.py:2080] To cancel the job:       sky cancel sky-spot-controller-9ce1ce58 17
I 10-04 15:56:40 cloud_vm_ray_backend.py:2080] To stream the logs:      sky logs sky-spot-controller-9ce1ce58 17
I 10-04 15:56:40 cloud_vm_ray_backend.py:2080] To view the job queue:   sky queue sky-spot-controller-9ce1ce58
I 10-04 15:56:40 cloud_vm_ray_backend.py:2189] 
I 10-04 15:56:40 cloud_vm_ray_backend.py:2189] Cluster name: sky-spot-controller-9ce1ce58
I 10-04 15:56:40 cloud_vm_ray_backend.py:2189] To log into the head VM: ssh sky-spot-controller-9ce1ce58
I 10-04 15:56:40 cloud_vm_ray_backend.py:2189] To submit a job:         sky exec sky-spot-controller-9ce1ce58 yaml_file
I 10-04 15:56:40 cloud_vm_ray_backend.py:2189] To stop the cluster:     sky stop sky-spot-controller-9ce1ce58
I 10-04 15:56:40 cloud_vm_ray_backend.py:2189] To teardown the cluster: sky down sky-spot-controller-9ce1ce58