Background/Async TEK submission (EXPOSUREAPP-3620) #2008

* Introduce lastSubmissionUserActivityUTC settings and use it as "skip condition" for the SubmissionTask

* Introduce background submission.

* Fix worker not being canceled.

* Disable auto submission is consent is not given.

* Cancel worker by tag.

* Introduce per TaskRequest error-handling.
Set SubmissionWorker deployed task requests to SILENT.

* Fix test regressions due to api change.

* Add SubmissionWorker test.

* Add AutoSubmissionTest.kt

* Don't reset retry attempt count and date when enabling MONITOR or SUBMIT_ASAP.
Otherwise would loose that data when the app is restarted despite it still "trying".
Only reset the data on DISABLED, i.e. when the task finishes or give sup.

* Add additional SubmissionTaskTest.kt related to automatic submission behavior.

* Remove unused value.

* Fix typo

* Return Result.retry() on exceptions.
We retry until we are successful, any abort conditions will be handled by the task.

* LINTs

* Fix test regression.