Upgrade to aws sdk 3

[gradam]

Hey
Would you be ok with upgrading to aws sdk 3?
Hardhat is currently complaining about sdk v2

$ npx hardhat clean --global                                                                                                                                                                
(node:9264) 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).

If you are willing to merge it i can create a PR!