fix: set optimizer_name in train_state when loading checkpoint without optimizer (#1203)

Author: loker404

python/train.py

@@ -780,6 +780,7 @@ def load():
 
             else:
                 logging.info("WARNING: Optimizer not found in state dict, using fresh optimizer")
+                train_state["optimizer_name"] = optimizer_name
 
             return (model_config, ddp_model, raw_model, swa_model, optimizer, metrics_obj, running_metrics, train_state, last_val_metrics)