[S3Store] 0 bytes files are not uploaded

[fenos]

Hello,
Currently, it seems that 0 bytes files don't make it to S3.
the .info file is written correctly and the request succeeds but no files are present on the S3 Bucket.

I guess there is a bug on the StreamSplitter but I yet need to do further investigation.
Feel free to look at this too as it might take me sometime

[Murderlon]

Posting how tusd handles it for my own reference later:

https://github.com/tus/tusd/blob/15f05c021c9770dc0cd2818aa4ef44b9e361f5b2/pkg/s3store/s3store.go#L839-L862