feat(services/s3): add append support

[Frank-III]

Which issue does this PR close?

Close: #5351

Are there any user-facing changes?

when writing to S3 Express One Zone, user can:

let writer = op.writer_with(path).append(true).await?;
writer.write(bs).await?;
writer.close().await?;

[Xuanwo]

Hi, checking with default_storage_class doesn't seem like a good idea to me. How about adding a new flag called enable_write_with_append? Users who confirm that they support append can enable this.

[Xuanwo]

Hi, I assume that only the first append call supports setting up metadata. We don't need to repeat the metadata for subsequent append requests.

[Frank-III]

Hi, so sorry for the late reply! having two crazy weeks after the holidays :(

I may not follow what you mean but it seems we could set up the metadata after the first one?