[API Server] Aggregated cluster info for all users is visible everywhere

[cblmemo]

On the API server deployed on a cloud VM, the sky status prints nothing but the sky status from client shows different outputs. An aggregated info for all client's clusters would be helpful.

[cblmemo]

I just found sky status -u that will print out all user's clusters. However, this seems can be accessed by all users without any permission requirements. Is that expected?

[cg505]

At this point, I believe it's an intentional decision to not try to do any authorization logic, for simplicity.