fix: extract content from image meta before uploading file

Author: liuruibin

apps/application/flow/step_node/document_extract_node/impl/base_document_extract_node.py

@@ -61,7 +61,8 @@ def save_image(image_list):
                     'application_id': str(application.id) if application.id else None,
                     'file_id': str(image.id)
                 }
-                f = bytes_to_uploaded_file(image.meta['content'], image.file_name)
+                file_bytes = image.meta.pop('content')
+                f = bytes_to_uploaded_file(file_bytes, image.file_name)
                 FileSerializer(data={
                     'file': f,
                     'meta': meta,