Inconsistency in README text

The results section for Ariane has the following text "The results below are reported for training from scratch, **since the pre-trained model cannot be shared at this time**.", which contradicts with "**We release a model checkpoint pre-trained on 20 TPU blocks, which can serve as a starting point for model training and fine-tuning purposes.** ".

Start in the README's Ariane results section and compare the two quoted statements about training from scratch and the released checkpoint. Reconcile the wording so the section no longer contradicts itself, then review the rendered README to confirm the result is clear.

Written by the indexing model from the issue text.