Add timestamps to [emr-cli] logs

Hi,

Do you think it's fine to have a basic understanding of how much time it took to proceed between stages and when the job was initially started, by looking only at the logs in the terminal?

The issue names no files, tests, or entry points. Start by locating the emr-cli command path that emits terminal logs and trace how job start and stage transitions are reported; done means the terminal logs show when the job started and the elapsed time between stages.

Written by the indexing model from the issue text.