[data] add dataloader for lance datasource

[Jay-ju]

Why are these changes needed?

The storage format of lance will be used in multimodal preprocessing and training. When used for training, it needs to be loaded by Dataloader. Here are two relatively important characteristics:

1. lance supports point query and can be randomly shuffled.
2. After lance is adapted to dataloader, it can load data in a streaming manner to prevent memory overflow and excessive loading time of training data.

Therefore, this provides how lance can form a Dataset for torch Dataloader implementation, enabling the unification of ray train and ray data.

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