Backup Telemetry: Ability to measure performance of backups

[mwang1026]

Describe the solution you'd like
As we're thinking about improving backup performance, we want to be able to know whether we've made those improvements or not. The ability to tie together:

• Throughput
• Size of the backup
• Where the backup is sent to
• Elapsed time

Additional context
At the end of the day, the goal is to understand the extent of our improvements. This may not be the answer. If there is another better way, let's open another issue and link + close this one.