registry: remove links to commercial support

Signed-off-by: Sebastiaan van Stijn <[email protected]>

registry/content.md

@@ -21,7 +21,3 @@ $ docker push localhost:5000/ubuntu
 The [documentation over at docs.docker.com](https://docs.docker.com/registry/) is a good place to learn more about what the registry is, how it works, and how to use it.
 
 Specifically, [the section regarding deployment](https://docs.docker.com/registry/deploying/) has pointers for more complex use cases than simply running a registry on localhost.
-
-# Support
-
-If you are interested in commercial support, the [Docker Trusted Registry](https://www.docker.com/docker-trusted-registry) provides an image registry, LDAP/Active Directory integration, security certificates, and more in a solution that includes commercial support.