Make sure prefetch tracking affects job readiness.

Make sure that marking the prefetch constraint as satisfied or not
actually impacts a job's readiness state.

Bug: 241107883
Test: atest CtsJobSchedulerTestCases
Test: atest frameworks/base/services/tests/mockingservicestests/src/com/android/server/job
Test: atest frameworks/base/services/tests/servicestests/src/com/android/server/job
Change-Id: I6f8dc887c8ba27f21809aefe2219b85265f1aa29