switch to aws-sdk-go-v2 as v1 is going away

[dims]

Context: https://aws.amazon.com/blogs/developer/announcing-end-of-support-for-aws-sdk-for-go-v1-on-july-31-2025/
Migration guide: https://aws.github.io/aws-sdk-go-v2/docs/migrating/

Basically maintenance mode on July 31, 2024 and reach end-of-support on July 31, 2025. The SDK will not
receive API updates for new or existing services, or be updated to support new regions.