[FEA] Easy functionality for using class_weights and sample_weights for Retrieval models

[rnyak]

🚀 Feature request

• Since Inbatch sampler converts the retrieval task to multi-class classification, we need an easy functionality to be able to use class_weight and sample_weight args in the model.fit() for retrieval models, without users to deal with customization.
• add unit test for using sample_weight and class_weight args for retrieval tasks in here
• we need examples or code snippets in the docs to showcase the functionality

This request comes from a customer.