DEV: Do not abort direct S3 uploads if upload_debug_mode enabled (PR #14141)

See the previous commit d66b258b0e9a635a67007b1d95d3d50475f662cf as well.

If enable_upload_debug_mode is true, we do not want to abort the direct S3 upload, because that will delete the file on S3 and prevent further inspection of any errors that have come up.


Totally unrelated frontend test failure.