Fix sample test workflow for PRs from forks

[rynowak]

Summary

The issue we have is that our sample containers get pushed to GHCR even when we're just doing testing. The problem is that a PR from a fork will not (and should not) have permission to push to our GHCR.

Ideal solution

PRs from a fork 'just work' without an approval step.

Non-ideal solution

PRs from a fork give the user permissions on our GHCR, and then require approval to run. This isn't great because now we have a manual approval step.

How we could do it

What if we didn't push the images to GHCR.

• We need a container registry that doesn't require permissions to read from.
• We need to be able to read from the container registry in the Github Agent as we run a k3d cluster in the agent.

We create the K3d cluster here.

Conveniently K3d has a built in feature-set for an internal container registry: https://k3d.io/v5.6.0/usage/registries/

Solution:

• Use K3d to create a local container registry that can be used from tests.
• Push images to local container registry.
• Parameterize the samples so that we can pass in the image reference. Here's an example of a hardcoded sample.
  • Add a new parameter that sets the image version.
  • Set the parameter default value to the current value.

AB#9864