Update bulk_upload.py

compressed_files relative import didn't point to the right location.

mayan/apps/sources/management/commands/bulk_upload.py

@@ -11,8 +11,7 @@ from documents.models import DocumentType
 from metadata.api import convert_dict_to_dict_list
 
 from ...models import OutOfProcess
-from ...compressed_file import NotACompressedFile
-
+from common.compressed_files import NotACompressedFile
 
 class Command(LabelCommand):
     args = '<filename>'