Use the ImageDigest SourcePolicy to configure image registry on bootstrap host

A new policy was added to the ImageDigestSource configuration that
allows the user to specify policy when there is a failure pulling
an image from the source.

Update the image registry configuration on the bootstrap host with
this SourcePolicy.

Author: sadasu

data/data/bootstrap/files/etc/containers/registries.conf.template

@@ -3,6 +3,7 @@
 location = "{{ $r.Endpoint.Location }}"
 insecure = {{ $r.Endpoint.Insecure }}
 mirror-by-digest-only = {{ $r.MirrorByDigestOnly }}
+blocked = {{ $r.Blocked }}
 
 {{ range $m := $r.Mirrors -}}
 [[registry.mirror]]

pkg/asset/imagebased/image/registriesconf.go

@@ -6,6 +6,7 @@ import (
 	"github.com/containers/image/v5/pkg/sysregistriesv2"
 	"github.com/pelletier/go-toml"
 
+	configv1 "github.com/openshift/api/config/v1"
 	"github.com/openshift/installer/pkg/asset"
 	"github.com/openshift/installer/pkg/asset/ignition/bootstrap"
 	"github.com/openshift/installer/pkg/types"
@@ -73,6 +74,7 @@ func (i *RegistriesConf) generateRegistriesConf(imageDigestSources []types.Image
 		registry := sysregistriesv2.Registry{}
 		registry.Endpoint.Location = group.Source
 		registry.MirrorByDigestOnly = true
+		registry.Blocked = group.SourcePolicy == configv1.NeverContactSource
 		for _, mirror := range group.Mirrors {
 			registry.Mirrors = append(registry.Mirrors, sysregistriesv2.Endpoint{Location: mirror})
 		}