Support for case insensitive properties in the aws credentials file

[debora-ito]

Originally reported in #4164.

Some SDKs (like Java, .NET, Javascript, Ruby) only support lowercase attributes in the aws credentials file, like:

[default]
aws_access_key_id=
aws_secret_access_key=
aws_session_token=

Uppercase properties like AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY are ignored by most SDKs - although it works fine in AWS CLI.

This is a feature request for support of case insensitive credentials file properties , in a consistent manner across all the SDKs.

Community note: please add a 👍 if you are interested in this.

[trevorstr]

I opened a bug for this today, for the Rust SDK. I wasted hours trying to figure out why the AWS CLI was working perfectly fine, but the Rust SDK wasn't.

awslabs/aws-sdk-rust#1020

[debora-ito]

Transferring back to the Java SDK 2.x repo.