[ECR] [Support for scanning scratch based images]: Finding vulnerabilities in scratch based images

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**Tell us about your request**
What do you want us to build? Support for scanning scratch based images

**Which service(s) is this request for?**
ECR

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
Find vulnerabilities in scratch based images

**Are you currently working around this issue?**
How are you currently solving this problem?

**Additional context**
Anything else we should know?

**Attachments**
If you think you might have additional information that you'd like to include via an attachment, please do - we'll take a look. (Remember to remove any personally-identifiable information.)

Start by reviewing the ECR request and the stated problem of finding vulnerabilities in scratch-based images. Clarify how scratch images should be scanned and define the expected vulnerability findings and completion criteria with the maintainers; the issue names no repository files or tests.

Written by the indexing model from the issue text.