BUG Fix log string formatting

Without this "%s", we see an error message for every fragment of multipart uploads.

Author: Stephen Hoover

CHANGELOG.md

@@ -6,6 +6,9 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Added
 - Added a script for integration tests (smoke tests).
 
+### Fixed
+- Added missing string formatting to a log emit in file multipart upload (#217)
+
 ### Changed
 - Updated CivisML 2.0 notebook (#214)
 - Reworded output of `civis notebooks new` CLI command (#215)

civis/io/_files.py

@@ -148,7 +148,7 @@ def _upload_part_base(item, file_path, part_size, file_size):
             msg = _get_aws_error_message(part_response)
             raise HTTPError(msg, response=part_response)
 
-        log.debug('Completed upload of file part', part_num)
+        log.debug('Completed upload of file part %s', part_num)
 
     # upload each part
     try: