Hi Andrew -
OOB, there is really no way to do this. You can obviously manage who has the concurrent licenses via License Management in IA, but that doesn't tell you who is Logged In with that license "right now". You'd have to look at that information, and then look into Supervisor and log that individual out manually (if you have the permission to do so).
That said though, what release are you running? In some of the later releases, new data sets were added that can assist with this task. However, some issues were corrected in 2018 R2 P 13. If you are running that release (and patch) or later, look into enabling the IC Application Login Logout Change Log (Log ID 9) and the Enhanced Interaction Administrator Change Notification Log (Log ID 6).
If those logs are enabled you could cross reference both to see not only who has what license, but also when they logged in. In the corresponding database tables, if you do not see a logout event, you know the user is still logged in.
Furthermore, you can also use that data to create custom reports, like the one below:
I hope this helps!
Thanks,
Trent.