Add mapping between SPDX AI and Dataset Profiles and MLCommons Croissant

[bact]

From 2025-01-22 AI meeting, we may like to have a mapping between SPDX Dataset fields and MLCommons Croissant for interop with major dataset platforms.

Croissant metadata format provides a vocabulary for dataset attributes, streamlining how data is loaded across ML frameworks such as PyTorch, TensorFlow or JAX. https://github.com/mlcommons/croissant

Croissant Format Specification 1.0
https://docs.mlcommons.org/croissant/docs/croissant-spec.html