train model with train_unified_conformer_ctl.yaml erros

[junshipeng]

@YYTtyy
File "***/wenet/utils/executor.py", line 136, in cv
) if _dict['th_accuracy'] is not None else 0.0)
KeyError: 'th_accuracy

主要是asr_model_ctl.py文件中forward函数返回的loss_dict中没有"th_accuracy": acc_att，导致executor.py中执行错误
total_acc.append(_dict['th_accuracy'].item(
) if _dict['th_accuracy'] is not None else 0.0)

[xingchensong]

可以直接提个PR修复

[YYTtyy]

ok 我这两天看看哈～