[BIC] Add integration tests

Add a host test BackgroundInstallControlServiceHostTest,
which sets up the environment and trigger an on-device
test, BackgroundInstallControlServiceTest.
The current version mainly test the GetMockBackgroundInstalledPackages
function of BICS.

Bug: 268111456
Test: atest BackgroundInstallControlServiceHostTest

Change-Id: I5a87194e9e87fbd85aef86608293ffdac72be221