push method
Push a job to the queue
Implementation
@override
Future<String> push(String queue, String payload) async {
final job = Job(
id: DateTime.now().millisecondsSinceEpoch.toString(),
queue: queue,
payload: payload,
createdAt: DateTime.now(),
);
_queues.putIfAbsent(queue, () => []).add(job);
return job.id;
}