fix(codepipeline): correctly validate Artifacts used by Actions in th…

[skinny85]

…e same Stage.

The bug was: we were incorrectly iterating though the Actions of a given Stage: first we were iterating through all of the Actions looking at their inputs, and then we looped through the Actions again to look at the outputs. But that won't work if the input of an Action is the output of a different Action in the same Stage with a lower runOrder. The fix is to iterate through all of the inputs of a given Action, and then the outputs, and only then move on to the next Action in increasing runOrder sequence in the same Stage.

Fixes #2549

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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.

[eladb]

please describe the fix in the PR message

[eladb]

What's up here?

[skinny85]

The bug is a validation error, so the expect is used only to trigger validation. This test fails without the production code changes.