Draft: Add a script file for custom exit code

What does this MR do and why?

Re: Map CI/CD failures to failure categories (#512594 - closed)

MR acceptance checklist

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Screenshots or screen recordings

Forced a failure in retrieve-tests-metadata

Which also triggered this Slack notification

I also forced 2 other failures:

• setup-test-env
• compile-test-assets

both received custom exit code

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.