Limit execution extension to important jobs.

Limit the timeout execution extension for apps in privileged states to
only the jobs that are marked as important.

Bug: 284512488
Bug: 299329948
Bug: 299346198
Test: atest FrameworksMockingServicesTests:QuotaControllerTest
Change-Id: Ie6d17f091ae18cd8ff402886ca7d9a9be3c56f07