compatibility with AWS SDK for JavaScript (v3)

[gibso]

express-sharp is currently implementing AWS SDK for JavaScript (v2), which, following to aws, will enter maintenance mode soon. There is a warning message saying:

(node:697) NOTE: We are formalizing our plans to enter AWS SDK for JavaScript (v2) into maintenance mode in 2023.

Please migrate your code to use AWS SDK for JavaScript (v3).
For more information, check the migration guide at https://a.co/7PzMCcy

It would be great to migrate this project to v3 then. Thank you!