Filter bucket list to use bucket-region parameter

[lusingander]

In #12, we fixed by getting bucket regions individually to filter the list.

However, since the ListBuckets API now supports specifying a region, it looks like this can be used.

https://aws.amazon.com/about-aws/whats-new/2024/10/amazon-s3-new-region-bucket-name-filtering-listbuckets-api

This is already supported by aws-sdk-rust:

https://github.com/awslabs/aws-sdk-rust/releases/tag/release-2024-10-16

So it seems better to fix to use this parameter.

I would like to confirm this, but I cannot test it in the AWS environment right now, and it is not yet supported by localstack, so I cannot confirm it.