Fix import error and add source_files to config

foundation_bert.py

@@ -145,6 +145,7 @@ class FoundationBert(BertModel):
             Modification to correctly handle loading extraneous parameters for GBert
         """
         model_config = Path(pretrained_model_name_or_path) / 'train_config.yaml'
+        print(f"🆘 {pretrained_model_name_or_path=}; {model_config=}")
         with open(model_config, 'r') as f:
             config = yaml.load(f, Loader=MyLoader)
         kwargs['modalities'] = config['modalities']