Add AWS credentials for loading S3 files in pipeline.yaml to data-prepper-config.yaml

Is your feature request related to a problem? Please describe.
Right now, to load files from S3 in pipelines.yaml in any plugin pipeline author has to provide AWS credentials in each plugin. This is making the pipeline look noisy. Currently we support loading ISM policy(ism_policy_file ) and index template(template_file) from S3.

Describe the solution you'd like
Leverage the extensions work and create an s3_configuration extension in data-prepper-config.yaml.

aws:
  # New configuration
  s3_configurations:
    authentication: my-custom-role
  credentials:
    default:
      sts_role_arn: arn:aws:iam::99123456789:role/OsiDataPlaneRole
      region: us-east-1
    my-custom-role:
      sts_role_arn:
      region:

Now, pipeline author don't have to configure the credentials in pipeline and just use S3 URI path to load files from S3.

log-pipeline:
  s3:
    aws:
      sts_role_arn: arn:aws:iam::123456789012:role/MyRole
      region: us-east-1
  sink:
    - opensearch:
        hosts: [""]
        ism_policy_file: "s3://filepath"