broken link fixes for bug#1476673

creating_images/custom.adoc

@@ -23,8 +23,7 @@ perfect match to fill that gap.
 A Custom builder image is a plain container image embedded with build process
 logic, for example for building RPMs or base container images. The
 `openshift/origin-custom-docker-builder` image is available on the
-https://registry.hub.docker.com/u/openshift/origin-custom-docker-builder[Docker
-Hub] as an example implementation of a Custom builder image.
+link:https://hub.docker.com/r/openshift/origin-custom-docker-builder/[Docker Hub] as an example implementation of a Custom builder image.
 
 Additionally, the Custom builder allows implementing any extended build process,
 for example a CI/CD flow that runs unit or integration tests. The only limit is