Updating ose-cluster-authentication-operator images to be consistent with ART

Reconciling with https://github.com/openshift/ocp-build-data/tree/da6a5af1fa96762cc8410f09fc28c0457280f59a/images/ose-cluster-authentication-operator.yml

Author: AOS Automation Release Team

.ci-operator.yaml

@@ -1,4 +1,4 @@
 build_root_image:
   name: release
   namespace: openshift
-  tag: rhel-8-release-golang-1.20-openshift-4.14
+  tag: rhel-8-release-golang-1.20-openshift-4.15

Dockerfile.rhel7

@@ -1,10 +1,10 @@
-FROM registry.ci.openshift.org/ocp/builder:rhel-8-golang-1.20-openshift-4.14 AS builder
+FROM registry.ci.openshift.org/ocp/builder:rhel-8-golang-1.20-openshift-4.15 AS builder
 WORKDIR /go/src/github.com/openshift/cluster-authentication-operator
 COPY . .
 ENV GO_PACKAGE github.com/openshift/cluster-authentication-operator
 RUN go build -ldflags "-X $GO_PACKAGE/pkg/version.versionFromGit=$(git describe --long --tags --abbrev=7 --match 'v[0-9]*')" -tags="ocp" -o authentication-operator ./cmd/authentication-operator
 
-FROM registry.ci.openshift.org/ocp/4.14:base
+FROM registry.ci.openshift.org/ocp/4.15:base
 COPY --from=builder /go/src/github.com/openshift/cluster-authentication-operator/authentication-operator /usr/bin/
 COPY manifests /manifests
 COPY vendor/github.com/openshift/api/operator/v1/0000_50_cluster-authentication-operator_01_config.crd.yaml /manifests/01_config.crd.yaml