For Windows, the container image's OS version must closely match the host's OS version.
For this reason, we need to add the --os-version annotation in image manifest lists,
so the Windows nodes can pull the appropriate image from the list.
Previously, the docker manifest CLI did not have the capability to set the --os-version,
it, but it has been introduced in docker 20.10.0.
We're also adding busybox.exe in the image, so we can run Linux commands inside the
container, so the tests will be simpler.
When building Windows images, a docker buildx builder needs to be created and used. When
building Windows images with docker buildx, the flag --output=type=registry is required,
otherwise it cannot be referenced on a Linux node.
Signed-off-by: Claudiu Belu <cbelu@cloudbasesolutions.com>
