Prevent Job Statuses from being calculated twice

#8435 introduced atomic eval
insertion iwth job (de-)registration. This change removes a now obsolete
guard which checked if the index was equal to the job.CreateIndex, which
would empty the status. Now that the job regisration eval insetion is
atomic with the registration this check is no longer necessary to set
the job statuses correctly.

nomad/state/state_store.go

@@ -4427,9 +4427,6 @@ func (s *StateStore) setJobStatus(index uint64, txn *txn,
 
 	// Capture the current status so we can check if there is a change
 	oldStatus := job.Status
-	if index == job.CreateIndex {
-		oldStatus = ""
-	}
 	newStatus := forceStatus
 
 	// If forceStatus is not set, compute the jobs status.