integration: rename registry binary

The skopeo_cidev image is updated with the registry binary from the
docker-distribution package instead of building one from source.

Ref: https://github.com/containers/automation_images/pull/410

Signed-off-by: Lokesh Mandvekar <lsm5@redhat.com>

integration/registry_test.go

@@ -13,7 +13,7 @@ import (
 )
 
 const (
-	binaryV2        = "registry-v2"
+	binaryV2        = "registry"
 	binaryV2Schema1 = "registry-v2-schema1"
 )