Updating ose-machine-api-provider-azure-container image to be consistent with ART

Reconciling with https://github.com/openshift/ocp-build-data/tree/4022cd290f00a44d667dda03f2d78d84a488c7ed/images/ose-machine-api-provider-azure.yml

Author: AOS Automation Release Team

.ci-operator.yaml

@@ -1,4 +1,4 @@
 build_root_image:
   name: release
   namespace: openshift
-  tag: rhel-9-release-golang-1.20-openshift-4.16
+  tag: rhel-9-release-golang-1.21-openshift-4.16

Dockerfile.rhel

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM registry.ci.openshift.org/ocp/builder:rhel-9-golang-1.20-openshift-4.16 AS builder
+FROM registry.ci.openshift.org/ocp/builder:rhel-9-golang-1.21-openshift-4.16 AS builder
 WORKDIR /go/src/github.com/openshift/machine-api-provider-azure
 COPY . .
 # VERSION env gets set in the openshift/release image and refers to the golang version, which interferes with our own