Refactor PredictionUDFs and LoadLocalModel so that LoadLocalModel constructs the bucketfs model file path

[MarleneKress79789]

We want to simplify the model loading and path management and also make future changes easier. To archive this, pull the bucketfs file path construction for the model from the HuggingFaceHubBucketFSModelTransferSP and BaseModelUDF into LoadLocalModel and supply the path to HuggingFaceHubBucketFSModelTransferSP for loading the model.