Configuration and credential files are a popular way of handling credentials for AWS. E.g. Red Hat IT provides a script that takes SSO credentials and writes a temporary AWS profile that can be used with AWS SDK. Let's add support for this in bib.

Goal:

• Implement a way for bootc-image-builder users to use their own configuration files instead of passing static credentials (AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY) via env variables.

• • The details (e.g. precedence between static credentials and profiles) should be as similar to the official AWS CLI as possible.

Acceptance Criteria:

• Users can use their profiles with bootc-image-builder.
  • Specifically, this must work with aws-saml.py.
• This is documented in bib's README.