Change pod name of federatedlearningjob to adapt feature extension

[davedavedavid]

What would you like to be added/modified: The name of the client pod "train" of federatedlearningjob can no longer cover the scope of the feature. eg, for , the client pod of collaberated training doesn't train at all. Please consider changing it to "client" or other proper name. Why is this needed:

[jaypume]

This variable was defined as workerParam.WorkerType at this line

[llhuii]

But the federated-learning definition is aggregationWorker/trainingWorkers indeed https://github.com/kubeedge/sedna/blob/main/pkg/apis/sedna/v1alpha1/federatedlearningjob_types.go#L41