------------------------
- Use ``boto3`` to handle ``credentials``, expanding and standardizing
authorization capabilities. This includes EKS IAM credentials that use
``AssumeRoleWithWebIdentity``.
- Enable opt-in caching of fetched on-demand credentials, to prevent rate
limiting.
- Make the ``pymongo_auth_aws.auth.aws_temp_credentials`` function public
so it can be used in ``pymongocrypt``.
Notes
.....
Because we are now using ``boto3`` to handle credentials, the order and
locations of credentials are slightly different from before. Particularly,
if you have a shared AWS credentials or config file,
then those credentials will be used by default if AWS auth environment
variables are not set. To override this behavior, set
``AWS_SHARED_CREDENTIALS_FILE=""`` in your shell or add
``os.environ["AWS_SHARED_CREDENTIALS_FILE"] = ""`` to your script or
application. Alternatively, you can create an AWS profile specifically for
your MongoDB credentials and set ``AWS_PROFILE`` to that profile name.