How to restrict assigning AOR only to HR department Employees?

Summary:

Restrict Assigning AOR to only HR Department Employees?

Content (required):

One of our customers has a Requirement.

They want “Employee Relations Manager” AOR should be restricted to HR department Employees.

When we are assigning  AOR from Person Management > Areas of Responsibility.

If the Employee belongs to HR department, then only AOR should display in the drop-down

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