Add on-hold monitor/notification

Description of the feature request

Some sort of notification/monitoring dashboard to see historically how often a build was on-hold.

Use case / for what or how I would use it

ATM we don’t have a good understanding if adding more concurrency will help us out. Ideally we’d like to know how often a build is “on hold”. If say we knew that throughout the week, there was at least one build “on hold” for a total of 5 hours, that would certainly prompt us to buy more concurrency.