feat(aws-stepfunctions): add support for AmazonSageMaker APIs

[mattmcclean]

Have updated the package @aws-cdk/aws-stepfunctions-tasks to include support for SageMaker APIs as per documentation here: https://docs.aws.amazon.com/step-functions/latest/dg/connect-sagemaker.html

Includes support for the following Amazon SageMaker API calls:

• CreateTrainingJob
• CreateTransformJob

Partially remediates #1314

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Pull Request Checklist

• Testing
  • Unit test added (prefer not to modify an existing test, otherwise, it's probably a breaking change)
  • CLI change?: coordinate update of integration tests with team
  • cdk-init template change?: coordinated update of integration tests with team
• Docs
  • jsdocs: All public APIs documented
  • README: README and/or documentation topic updated
  • Design: For significant features, design document added to design folder
• Title and Description
  • Change type: title prefixed with fix, feat and module name in parens, which will appear in changelog
  • Title: use lower-case and doesn't end with a period
  • Breaking?: last paragraph: "BREAKING CHANGE: <describe what changed + link for details>"
  • Issues: Indicate issues fixed via: "Fixes #xxx" or "Closes #xxx"
• Sensitive Modules (requires 2 PR approvers)
  • IAM Policy Document (in @aws-cdk/aws-iam)
  • EC2 Security Groups and ACLs (in @aws-cdk/aws-ec2)
  • Grant APIs (only if not based on official documentation with a reference)

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license.

[rix0rrr]

Wow, lots of work! Thanks!

Probably made a lot harder by the fact that we don't have SageMaker L2s yet (which also makes some points of the review moot).

Given that I have no experience with SageMaker, nor the time to learn about it right now, I'm inclined to just ship this as-is and let usage and review comments sort out how well it's working.

Can you please mark all new interfaces and classes with an

/**
 * @experimental
 */

In the docstrings?

[mattmcclean]

Have marked all new interfaces and classes with @experimental