fix(GODT-3124): Handling of sync child jobs

Improve the handling of sync child jobs to ensure it behaves correctly
in all scenarios.

The sync service now uses a isolated context to avoid all the pipeline
stages shutting down before all the sync tasks have had the opportunity
to run their course.

The job waiter now immediately starts with a counter of 1 and waits
until all the child and the parent job finish before considering the
work to be finished.

Finally, we also handle the case where a sync job can't be queued
because the calling context has been cancelled.

internal/services/syncservice/job_test.go

@@ -83,6 +83,7 @@ func TestJob_WaitsOnAllChildrenOnError(t *testing.T) {
 
 		job1.onFinished(context.Background())
 		job2.onError(jobErr)
+		tj.job.end()
 	}()
 
 	close(startCh)
@@ -115,6 +116,7 @@ func TestJob_MultipleChildrenReportError(t *testing.T) {
 	}
 
 	wg.Wait()
+	tj.job.end()
 	close(startCh)
 	err := tj.job.waitAndClose(context.Background())
 	require.Error(t, err)
@@ -179,6 +181,7 @@ func TestJob_CtxCancelCancelsAllChildren(t *testing.T) {
 
 	go func() {
 		wg.Wait()
+		tj.job.end()
 		cancel()
 	}()
 
@@ -201,6 +204,7 @@ func TestJob_CtxCancelBeforeBegin(t *testing.T) {
 	go func() {
 		wg.Wait()
 		cancel()
+		tj.job.end()
 	}()
 
 	wg.Done()