Add support for loading torchscript models

[AnandInguva]

Adding support for loading models that are saved in torchscript format

More details at https://pytorch.org/tutorials/beginner/saving_loading_models.html#export-load-model-in-torchscript-format

This will enable the users to load the whole model without requiring model class.

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GitHub Actions Tests Status (on master branch)

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[codecov]

Codecov Report

Merging #25321 (e5c9062) into master (bf3710c) will decrease coverage by 0.09%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master   #25321      +/-   ##
==========================================
- Coverage   72.93%   72.85%   -0.09%     
==========================================
  Files         748      750       +2     
  Lines       99366    99484     +118     
==========================================
+ Hits        72473    72476       +3     
- Misses      25525    25640     +115     
  Partials     1368     1368              

Flag	Coverage Δ
python	82.25% <0.00%> (-0.14%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...thon/apache_beam/ml/inference/pytorch_inference.py	0.00% <0.00%> (ø)
...ache/beam/model/fn_execution/v1/beam_fn_api_pb2.py	100.00% <0.00%> (ø)
...xamples/inference/onnx_sentiment_classification.py	0.00% <0.00%> (ø)
.../python/apache_beam/ml/inference/onnx_inference.py	0.00% <0.00%> (ø)
...on/apache_beam/runners/dataflow/dataflow_runner.py	81.88% <0.00%> (+0.14%)	⬆️
...python/apache_beam/runners/worker/worker_status.py	76.66% <0.00%> (+1.33%)	⬆️

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[AnandInguva]

Run PythonLint PreCommit

[AnandInguva]

R: @damccorm

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[damccorm]

Thanks for adding this!

[damccorm]

LGTM, I'll merge once checks pass

[AnandInguva]

LGTM, I'll merge once checks pass

I think there are some lint issues(not clear why they appear). I will tackle them tomorrow and will ping you.

[AnandInguva]

@damccorm The tests pass but for some reason they are not updated in UI. PTAL

[damccorm]

Run Whitespace PreCommit

[damccorm]

LGTM pending checks passing