Support for user-agent-prefix setting

[m-revetria]

With AWS SDK, it is possible to set the property Configuration#user_agent_prefix which will be used for every request against AWS services.

Currently, the project I'm working on needs to set this property in order to comply with AWS, they has requested that we identify requests that we make to our users' S3 resources on their behalf so they can assess our impact. The way to identify our requests is by using a custom value for HTTP User-Agent header

[github-actions]

This issue has been automatically marked as stale because it has been open 90 days with no activity. Remove stale label or comment or this issue will be closed in 30 days

[github-actions]

This issue has been automatically marked as stale because it has been open 90 days with no activity. Remove stale label or comment or this issue will be closed in 30 days