Mocking the PackageManager while ConnectivityService is running
could throw an UnfinishedStubbingException. This change splits
the test into two distinct tests that don't need to change the
mocking value for PackageManager during testing.
Fix: 433600031
Test: atest ConnectivityServiceTest
Flag: TEST_ONLY
Change-Id: Ibcff2082d1e50e89c272573b4c719a7325c959fd