SystemServer: use test cache in test

The test does not run as the SystemServer. Therefor it can't invalidate
cache due to se policy. We need the unit test to use a fake cache

Test: atest ServiceBluetoothTests
Bug: 362569584
Flag: com.android.bluetooth.get_state_from_system_server
Change-Id: If81c0d359f467a3ceed601a6208fde188b9d96ee