Define CAR_TEST_SERVICE permission in CtsPermission2TestCases

- Add permission definition of CAR_TEST_SERVICE.
- Add test to make sure that no pre-installed apps use CAR_TEST_SERVICE
permission

Bug: 145390708
Test: Run
android.permission2.cts.PermissionPolicyTest#testPlatformPermissionPolicyUnaltered
and android.car.cts.PermissionTest#testNoCarTestServicePermission.

Change-Id: If4730126c9dd6fe675e27137ec38e152d80580a9
Merged-In: If4730126c9dd6fe675e27137ec38e152d80580a9
2 files changed