Prevent NPE in CoreSettingsObserverTest

The constructor of AppBatteryTracker#AppBatteryPolicy updated in a
commit [1] and now that the test need to be changed, similar to another
previous commit [2].

[1] Iffa7ff2b7fb8f14f1a54359d72d936c721d27904
[2] I2f808828eba79147fea3a88279effffb7b5b20a4

Bug: 245454635
Test: CoreSettingsObserverTest
Change-Id: I1e890e93868b605fe9c413a8749c694d6f59c1c3
1 file changed