s3 concurrent uploader will overwrite the real error

[lance6716]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

io: read/write on closed pipe

see the unit test in #48163

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)