Admission plugin to limit concurrent login tokens

1. Proposed title of this feature request

Admission plugin to limit concurrent login tokens

2. What is the nature and description of the request?

There is currently no way to limit concurrent login, we want to use have a solution to at least have a soft limit on concurrent logins, and in this case as suggested in control plane meeting an admission plugin will be sufficient.

3. Why does the customer need this? (List the business requirements here)

In order to meet FedRAMP control AC-10, we need to be able set a limit on maximum number of concurrent sessions.

Related Jira Task: CMP-1001