feat(virtualpackage.yaml): Add new virtualpackage test pipeline with example usage

[philroche]

Based on provider-priority and the same name provided by other packages, it was determined we have many virtual packages that should never be installed.

Instead one of the providing packages should be installed.

This package test ensures this remains true and does not regress.

Virtual package is defined as a package that has another package providing the exact same name with a higher provider priority.

This is tracked @ https://github.com/wolfi-dev/os/issues/44820 and internal to chainguard @ https://github.com/chainguard-dev/internal-dev/issues/12573

Signed-off-by: philroche [email protected]