bug: improper handling for s3 copy response

### Describe the bug Same as https://github.com/apache/opendal/issues/7293, my fix got overwritten in the recent S3 copy operation rewrite. ### Steps to Reproduce N/A ### Expected Behavior N/A ### Additional Context _No response_ ### Are you willing to submit a PR to fix this bug? - [x] Yes, I would like to submit a PR.