Fix JobThrottling tests, take 2.

1. Reset execution quotas between tests so earlier run tests don't
affect later ones.
2. Ensure uidActive overrides even the NEVER bucket. Also log a wtf if
we ever get into this situation.

Bug: 138253466
Bug: 149931359
Test: atest android.jobscheduler.cts.JobThrottlingTest
Change-Id: I1caf92fe8dda3c661ef68ca56c32fcd709e26856