[ECR/Inspector] [request]: Support Alpaquita Linux in enhanced scanning

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**Tell us about your request**
Alpaquita Linux is an Alpine derivate linux distribution by BellSoft optimised for running in containers, providing an optimised experience for JVM-based applications: https://bell-sw.com/alpaquita-linux/. Despite being Alpine/apk-based, AWS ECR fails to scan images based on Alpaquita due to "an unsupported OS". It would be very helpful if such images could be scanned in future.

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

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
We aim at building the smallest container images possible while profiting from a small attack surface and fast updates to open CVEs. Alpaquita seems a like good choice for this.

**Are you currently working around this issue?**
Using vanilla Alpine, but we're thinking of switching to a different image scan tooling that supports Alpaquita.

No repository files, tests, or entry points are identified in the issue. Start by reviewing the ECR enhanced scanning request and Alpaquita Linux compatibility details; done means Alpaquita-based images are accepted and scanned instead of reported as having an unsupported OS.

Written by the indexing model from the issue text.