Fix a bug in AnomalyDetectionJobService

Even though onStopJob is called, the service may still exist, so
we need to reset the mIsJobCanceled in onStartJob

Also remove the batteryStats since we don't need it anymore.

Change-Id: I6d48efecb750ad4e464569cac426d87014a8db90
Fixes: 77968649
Test: RunSettingsRoboTests