fix: labels.sha write belongs to distill_sequence only (logit-KD has no labels file)

Author: Ronald Tse

src/gpu/modal_distill.py

@@ -399,7 +399,6 @@ def val_loss() -> float:
             if step % save_every == 0:
                 ck = out_root / f"step-{step}"
                 ck.mkdir(exist_ok=True)
-                (ck / "labels.sha").write_text(labels_digest)
                 torch.save(student.state_dict(), ck / "student.pt")
                 torch.save(optimizer.state_dict(), ck / "optim.pt")
                 CHECKPOINTS.commit()