Unpinned s3fs pulls in an ancient and slow version

Installing latest LLMeter on a fresh environment pulls in `s3fs==0.4.2` ([from 2020](https://github.com/fsspec/s3fs/releases/tag/0.4.2)) - and using S3 features raises the following warning:

```
UserWarning: Your installed version of s3fs is very old and known to cause
severe performance issues, see also https://github.com/dask/dask/issues/10276

To fix, you should specify a lower version bound on s3fs, or
update the current installation.

warnings.warn(s3_msg)
```

As mentioned in the cited thread, it seems like this is caused how dependency resolvers handle the vastly different release frequencies of s3fs, aiobotocore, and botocore/boto3.

Maybe LLMeter should pin s3fs at some reasonable compromise minimal version (e.g. `>=2023`?) to avoid the issue?

Start by locating LLMeter's dependency declarations and reproduce a fresh installation of the latest release. Check how the resolver selects s3fs alongside aiobotocore and botocore/boto3, then choose and document a lower bound that avoids the reported old-version warning. Confirm that using S3 features no longer emits the warning.

Written by the indexing model from the issue text.