Rename empty to abandoned Jobs

This is to better reflect the purpose of this feature.
Abandoned jobs cannot be accurately determined. Hence we
cannot force finish them. However we can report them to
the client and take less disruptive actions post detection.

Additionally, change the feature flag to roll out the
modified version of this feature

bug: 372529068
Test: Existing CTS and unit tests pass
Flag: android.app.job.handle_abandoned_jobs
Change-Id: Ic6dc8bbe66cd9011da098fe5d6c8255f82d4c5e2