Update comment on release.sh to reflect new release repo

build/release.sh

@@ -16,8 +16,10 @@
 
 # Build a Kubernetes release.  This will build the binaries, create the Docker
 # images and other build artifacts.
-# For pushing these artifacts publicly on Google Cloud Storage, see the
-# associated build/push-* scripts.
+#
+# For pushing these artifacts publicly to Google Cloud Storage or to a registry
+# please refer to the kubernetes/release repo at
+# https://github.com/kubernetes/release.
 
 set -o errexit
 set -o nounset