Add worker_beat service

[tmokmss]

We might not need this but it can be used for automatic plugin version upgrade.

https://github.com/langgenius/dify/blob/2a84832998b4a005373859a82919a62a1bbbec42/docker/docker-compose-template.yaml#L58-L75

See langgenius/dify#19758