Prepare testdata for "apko on top of base image"

[sfc-gh-mhazy]

Overview

• Added more packages and split them into 2 repositories to simulate one being private.
• Prepared base image that uses packages from both repositories
• Refreshed preexisting testdata.

Context

#806

The package dependency graph is the following

(repo 1)  baselayout <---- replayout
              ^
              |
(repo 2)  package-x  <---- package-y

The base image apko build declares package-y, so after resolving, image contains package-y, package-x and baselayout

In the future the "top" image will be on top of base and will add replayout.

Commands for testdata generation

In base_packages directory:

melange build package-y.melange.yaml --signing-key=private_pkg_key.rsa
melange build package-x.melange.yaml --signing-key=private_pkg_key.rsa

In testdata directory:

apko build base_image.apko.yaml golden:latest base_image/

[sfc-gh-mhazy]

@jonjohnsonjr mind taking a look?