[code-reflection] RFR: Updating the ONNX CNNTest

[duke]

On Wed, 5 Feb 2025 16:09:36 GMT, Adam Pocock <duke at openjdk.org> wrote:

> - Adds a Python script which trains a small LeNet style CNN on MNIST, exporting it to ONNX format.
> - Updates the CNNTest to match the trained CNN.
> - Added support for loading in the ONNX model, extracting the weights and saving them out in serialized Java records (this adds protobuf-java as a dependency along with the compiled ONNX protobuf).
> 
> The compiled ONNX protobuf is Apache 2.0 licensed, and the Python script is adapted from a PyTorch tutorial which is BSD licensed.

@Craigacp 
Your change (at version 89e445a76f1de5ac3bf89a4a858dc794196f2ee5) is now ready to be sponsored by a Committer.

-------------

PR Comment: https://git.openjdk.org/babylon/pull/307#issuecomment-2649056577