[FEATURE] Migrate TensorFlow algorithms to PyTorch

Description

Curent TF algos:

 Here are the TensorFlow-based models in the repo:

  ┌────────────┬──────────────────────────────────────────────────────────────────────────────┐
  │ Subpackage │                                    Models                                    │
  ├────────────┼──────────────────────────────────────────────────────────────────────────────┤
  │ deeprec    │ XDeepFM, DKN, DKN_Item2Item, LightGCN, GRU, Caser, A2SVD, NextItNet, SLI_REC │
  ├────────────┼──────────────────────────────────────────────────────────────────────────────┤
  │ newsrec    │ NAML, NRMS, NPA, LSTUR                                                       │
  ├────────────┼──────────────────────────────────────────────────────────────────────────────┤
  │ ncf        │ Neural Collaborative Filtering                                               │
  ├────────────┼──────────────────────────────────────────────────────────────────────────────┤
  │ vae        │ MultinomialVAE, StandardVAE                                                  │
  ├────────────┼──────────────────────────────────────────────────────────────────────────────┤
  │ rbm        │ Restricted Boltzmann Machine                                                 │
  └────────────┴──────────────────────────────────────────────────────────────────────────────┘

  That's 5 subpackages with ~17 model implementations total. The deeprec and newsrec packages are the largest, each with their own base class hierarchy. Most use
  TF 1.x compatibility mode (tf.compat.v1), while newsrec uses Keras.

Expected behavior with the suggested feature

Working in PyTorch

Willingness to contribute

• Yes, I can contribute for this issue independently.
• Yes, I can contribute for this issue with guidance from Recommenders community.
• No, I cannot contribute at this time.

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