A test api to override carrier information

This API should only be used for testing purpose e.g., CTS/GTS/SL4A
By overriding carrier information, we could force a particular carrier id,
carrier's config, but also any country or carrier overlays to be loaded
when using a test SIM with a call box.

Bug: 72332597
Test: atest CtsTelephonyTestCases:CarrierIdentificationTest

Change-Id: I32fa202597b69e6eba11e86bd1096e5f1bf1a639