core: split out all logic that updates a Job on a unit's unit_notify() invocation
Just some refactoring, no change in behaviour.
(cherry picked from commit 16c74914d233ec93012d77e5f93cf90e42939669)
Related: #1737283
patch_name: 0378-core-split-out-all-logic-that-updates-a-Job-on-a-uni.patch
present_in_specfile: true
location_in_specfile: 378
squash_commits: true