Updating Brew images to have both tag and shas

Dockerfile

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM brew.registry.redhat.io/rh-osbs/openshift-golang-builder:rhel_9_1.21 AS builder
+FROM brew.registry.redhat.io/rh-osbs/openshift-golang-builder:rhel_9_1.21@sha256:98a0ff138c536eee98704d6909699ad5d0725a20573e2c510a60ef462b45cce0 AS builder
 ENV APP_ROOT=/opt/app-root
 ENV GOPATH=$APP_ROOT
 
@@ -29,7 +29,7 @@ RUN go build -ldflags "${SERVER_LDFLAGS}" ./cmd/timestamp-server
 RUN CGO_ENABLED=0 go build -gcflags "all=-N -l" -ldflags "${SERVER_LDFLAGS}" -o timestamp-server_debug ./cmd/timestamp-server
 
 # Multi-Stage production build
-FROM brew.registry.redhat.io/rh-osbs/openshift-golang-builder:rhel_9_1.21 as deploy
+FROM brew.registry.redhat.io/rh-osbs/openshift-golang-builder:rhel_9_1.21@sha256:98a0ff138c536eee98704d6909699ad5d0725a20573e2c510a60ef462b45cce0 as deploy
 
 # Retrieve the binary from the previous stage
 COPY --from=builder /opt/app-root/src/timestamp-server /usr/local/bin/timestamp-server