Add the Ability to Lookup Last Time a Credential Was Utilized

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

This particular task is to automate identifying unused AAP credentials so that customers can perform the housekeeping and clean them periodically.

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

A ton a credentials are left in AAP and it's difficult to know which ones are still used.

1. How would you like to achieve this? (List the functional requirements here)

In the same way when a Credential is modified, let's show a "last-utilized" timestamp.
Implementation tbd by engineering

1. List any affected known dependencies: Doc, UI etc..

N/A

1. Github Link if any

https://github.com/ansible/awx/issues/7639