Preprocess: Fix refactor error not caught by tests

Author: p12tic

preprocess.py

@@ -47,7 +47,7 @@ def main():
     with concurrent.futures.ProcessPoolExecutor() as executor:
         futures = [executor.submit(preprocess.preprocess_html_file, root, fn,
                                    rename_map)
-                   for fn in enumerate(file_list)]
+                   for fn in file_list]
 
         for future in futures:
             output = future.result()