[S3] Log original error code for transient errors

[npow]

Currently, it's difficult to tell why transient S3 operations are retrying. Added the original error code to the logs.

Example:

Transient S3 failure (attempt #1) -- total success: 1, last attempt 1/2 -- remaining: 1 (ParamValidationError)
Transient S3 failure (attempt #2) -- total success: 1, last attempt 0/1 -- remaining: 1 (ParamValidationError)
Upload result: []

[Copilot]

Pull Request Overview

This PR enhances S3 operation error logging by including the original error code in transient error messages. This makes it easier to debug and understand why S3 operations are retrying instead of just knowing they failed transiently.

• Modified error handling to capture and log original error codes for transient failures
• Updated result parsing to handle the additional error code information
• Enhanced retry logging to display the specific error type causing the transient failure

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
metaflow/plugins/datatools/s3/s3op.py	Modified error handling to write error codes to result files and updated parsing logic to extract transient error types
metaflow/plugins/datatools/s3/s3.py	Enhanced retry logging to display the original error code that caused the transient failure

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[romain-intel]

Two minor nits. Did all the tests run internally too? If so, we can merge.

[npow]

Two minor nits. Did all the tests run internally too? If so, we can merge.

yes all good: https://github.netflix.net/corp/mli-metaflow-custom/pull/1388