AWS Default Credentials Chain not fetched in > 2.0.0

[nishkrishnan]

As of this PR:
#177

AWS Default Credentials Provider is never used so now we're forced to either pass in an access key/secret key or pass in a role to assume. However, the default credentials provider is much more flexible:
https://aws.github.io/aws-sdk-go-v2/docs/configuring-sdk/#specifying-credentials

In our case, we use web identity auth which is now broken.

[hbollon]

Hey @nishkrishnan !
Thanks for your issue, I plan to migrate from aws-sdk-go to aws-sdk-go-v2 in the near future. I will replace NewSession() by LoadDefaultConfig(), it should resolve your case.

[chrispruitt]

@hbollon any concerns with the linked pull request? This will fix the issue until you update the AWS SDK and is backward compatible. Also, happy to adjust if you see an issue with it. Thanks!