Add hours used to each User row

To aid in the identification of unused licenses or adoption barriers, let's use the work in #3735 to present the number of connection hours each user has in the Users listing.

<img width="1411" alt="image" src="https://user-images.githubusercontent.com/7416144/187562308-4b76ec9f-10d9-4b01-acf3-ab27be688a09.png">
