Testing external bash scripts using roles

How to run this test:

0. Ensure you have default credentials in your AWS CLI locations and edit the aws.config file to reference a role that can be assume by your default credentials.
1. terraform init
2. terraform apply will use your default credentials and will output the caller identity as such
3. AWS_PROFILE=foo AWS_CONFIG_FILE=aws.config terraform apply will use the profile foo mentioned in the aws.config file and will output the caller identity as such