feat(realms): docker hub-staging metadata

Signed-off-by: Alano Terblanche <18033717+Benehiko@users.noreply.github.com>

Author: Benehiko

x/realms/docker.go

@@ -19,5 +19,9 @@ var (
 	DockerRegistryStagingAuthentication = secrets.MustParsePattern("docker/auth/registry/docker-staging/**")
 )
 
-// DockerHubAuthenticationMetadata is a pointer to the default user signed in to Docker
-var DockerHubAuthenticationMetadata = secrets.MustParsePattern("docker/auth/metadata/hub/**")
+var (
+	// DockerHubAuthenticationMetadata is a pointer to the default user signed in to Docker
+	DockerHubAuthenticationMetadata = secrets.MustParsePattern("docker/auth/metadata/hub/**")
+	// DockerHubStagingAuthenticationMetadata is a pointer to the default staging user signed in to Docker
+	DockerHubStagingAuthenticationMetadata = secrets.MustParsePattern("docker/auth/metadata/hub-staging/**")
+)