Fix Spark-DL notebooks for CI/CD and update to latest dependencies

[rishic3]

Changes:

Version updates:

• Updated all examples to run with latest Triton (24.08), Tensorflow (2.17.0), and Torch (2.4.1), and match updated APIs.
• Notable changes:
  • Using new .keras model format in Tensorflow wherever applicable
  • Added use of Torch-TensorRT compilation/inference locally and on Spark to PyTorch notebooks

    Environment separation:

• Updated README for instructions on creating separate environments for Torch/Tensorflow to avoid CUDA conflicts.
• Separated Huggingface examples into _torch/_tf versions for environment separation, and demonstrate model interoperability.

  CI/CD:

• Included Spark Session initialization to work with CI/CD pipeline.
• Verified that all notebooks run error-free with jupyter nbconvert.

[rishic3]

@eordentlich @leewyang requesting a review - thanks!