Introduce SystemAuthority API for EnforcingAdmin

This new SystemAuthority API will be used by DPM to represent system
authorities that enforce policies or user restrictions.

Add unit tests to verify the functionality for EnforcingAdmin. Fix the
bug related to RoleAuthority where the roles are not parced to internal
EnforcingAdmin from parcelable one.

Update checks for advanced protection with SystemAuthority.

Bug: 414733570
Test: atest FrameworksServicesTests:com.android.server.devicepolicy.EnforcingAdminTest
Flag: EXEMPT refactor and bugfix

Change-Id: Ia7f51241719d56f67b8d9606b67b53c9ac872fb6