[Tests] Add example tests to cover `compress_xxx.py` scripts in compressed-tensors

[dsikka]

Is your feature request related to a problem? Please describe.

Add tests to run and validate the examples under compressed-tensors, starting with all the scripts compress_xxx.py (should include 4 scripts) https://github.com/vllm-project/compressed-tensors/tree/main/examples

Describe the solution you'd like

The tests should run the examples, validate that it runs end-to-end and do basic sanity checks on the output product (i.e should include safetensors file, should include a config.json with the quantization_config correctly filed out). The tests should live in the compressed-tensors repo.

[giovannicozzolongo]

Hi, I'd like to take this. Could you assign it to me?

[therealruthvik]

Hi @dsikka — I'm interested in this issue too.

My plan: add pytest cases under compressed-tensors/tests that run each compress_xxx.py example end-to-end and check for the safetensors file and a correctly populated config.json.

[dsikka]

@giovannicozzolongo