Update upstream Dockerfile

Root Dockerfile currently uses ocp builder image
Use openshift/release image instead

Author: kevinrizza

Dockerfile

@@ -1,5 +1,5 @@
 
-FROM registry.svc.ci.openshift.org/ocp/builder:golang-1.10 AS builder
+FROM registry.svc.ci.openshift.org/openshift/release:golang-1.10 AS builder
 WORKDIR /go/src/github.com/operator-framework/operator-marketplace
 COPY . .
 RUN make osbs-build