Avoid spammy adjustCallback iterations.

Add a delay to calling maybeAdjustRegisteredCallbacks in some instances
so that we don't spin doing the same work with no substantial change.

Bug: 141645789
Bug: 184740668
Test: atest frameworks/base/services/tests/servicestests/src/com/android/server/job
Test: atest frameworks/base/services/tests/mockingservicestests/src/com/android/server/job
Test: atest CtsJobSchedulerTestCases
Change-Id: I39890192b3e96476e7416e046581e45eb7a20060