Merge branch 'master' into replace_azure

convlab/nlg/evaluate_unified_datasets.py

convlab/nlg/scgpt/evaluate.sh

convlab/nlg/scgpt/main.py

convlab/nlg/scgpt/model.py

convlab/nlg/scgpt/multiwoz/__init__.py

convlab/nlg/scgpt/multiwoz/preprocess.py

convlab/nlg/scgpt/multiwoz/run.py

convlab/nlg/scgpt/scgpt.py

convlab/nlg/scgpt/scgpt_special_tokens.py

convlab/nlg/scgpt/train.sh