release-manifest points to internal registry

[mslacken]

When trying to build an image, the manifest is pulled form
oci://registry.opensuse.org/home/adinov/core/containerfile/release-manifest:0.0.1'
and this manifest points to
registry.suse.de
which is a internal registry and it not accesible from e.g. a freshly install VM

[atanasdinov]

Hi, @mslacken. We added quite a lot to our documentation recently, PTAL here.