Use enterprise cluster
Use enterprise cluster

This bumps the version of compose-broker to support compose enterprise
clusters.

This also hardcodes the name of our enterprise cluster as we feel it's a
simplest and most clear thing we can do.

alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf