[Spot] Add a way to show zone history of the spot job

[Michaelvll]

A user requested to have a functionality to show the zone history of the spot job, so that they can debug the performance issue more easily.

TODOs:

• Add cloud/zone information in the environment variable
• Add a CLI to check the zone history

[concretevitamin]

Maybe we should track Zone IDs too, for better tracking of real prices:

• Zone names are account-specific: us-east1-a [pls check spellings]
• Zone IDs are underlying IDs: use1-a, use1-b [pls check spellings]

[infwinston]

a doc for reference, https://docs.aws.amazon.com/ram/latest/userguide/working-with-az-ids.html

[Michaelvll]

This should be addressed by #1669