Missing test cases

[volcacius]

Issue to track areas with missing tests that should be added.

• Handling of scaling_min_val combined with different restrictions on scale factors.
• Calibration of activations scale factors during PTQ
• Bias correction during PTQ
• End-to-end test for PTQ
• Symbolic/Value Tracing
• Shapes of quant metadata when QuantTensor goes through view/flatten, etc.
• GPxQ tests Fix (gpxq): handling empty tensors with GPxQ and adding unit tests #892
• Learned Round tests
• Entrypoint for quantization of torchvision (i.e., testing that all flags and combinations are correct): progress tracked in Adding tests for "quantize" function for CNN PTQ #908
• Entrypoint for quantization of LLM (i.e., testing that all flags and combinations are corre

[Giuseppe5]

@i-colbert Could you help with some tests on GPxQ?