Can we configure popup messages on the user screen when user tries to submit termination

Summary:

As bydefault system allows submitting termination on the resigned employee, we want to build restriction to stop users from terminating resigned employee.

A pop-up message to come up only on the user's window (no email no other notification trigger), as soon as the user tries initiating another exit process(Termination) on an employee who's exit(Resignation) is already in progress.

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