GH-44334: [C++] Fix S3 error handling in ObjectOutputStream

[OliLay]

Rationale for this change

See #GH-44334. Errors from the AWS SDK are not correctly propagated onto the user of the ObjectOutputStream, not indicating an error even though there was one in some cases.

What changes are included in this PR?

• Directly pass the outcome of the AWS SDK to HandleUploadUsingSingleRequestOutcome aswell as HandleUploadPartOutcome instead of wrapping it in a arrow Result class which has been constructed implictily, always indicating success.
• Adjust cleanup handling in Close so that the output stream is closed if there was an error in any of the called methods. Otherwise, destructing the output stream in debug builds fails as we abort if Close() returns something else than Status::OK(). See the code pointer here.

Are these changes tested?

• Added assertions for catching exceptions on Close() in case delayed_open is enabled.

Are there any user-facing changes?

No.

• GitHub Issue: [C++][FS][S3] Errors in AWS SDK are not propagated correctly #44334

[github-actions]

⚠️ GitHub issue #44334 has been automatically assigned in GitHub to PR creator.

[OliLay]

FYI @pitrou This is related to #41564

[pitrou]

Nice catch, thank you @OliLay !

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 4 benchmarking runs that have been run so far on merge-commit c50c4fa.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details. It also includes information about 4 possible false positives for unstable benchmarks that are known to sometimes produce them.