test images: ARG instructions should be first

A few other Dockerfiles had the ARG duplicated as well.

Author: claudiubelu

test/images/node-perf/npb-ep/Dockerfile

@@ -34,7 +34,6 @@ RUN make EP CLASS=D
 # main container in the second build stage.
 RUN mkdir -p /lib-copy && find /usr/lib -name "*.so.*" -exec cp {} /lib-copy \;
 
-ARG BASEIMAGE
 FROM $BASEIMAGE
 
 COPY --from=build_node_perf_npb_ep /NPB3.3.1/NPB3.3-OMP/bin/ep.D.x /

test/images/node-perf/npb-is/Dockerfile

@@ -36,7 +36,6 @@ RUN make IS CLASS=D
 # main container in the second build stage.
 RUN mkdir -p /lib-copy && find /usr/lib -name "*.so.*" -exec cp {} /lib-copy \;
 
-ARG BASEIMAGE
 FROM $BASEIMAGE
 
 COPY --from=build_node_perf_npb_is /NPB3.3.1/NPB3.3-OMP/bin/is.D.x /

test/images/sample-apiserver/Dockerfile

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+ARG BASEIMAGE
 FROM us.gcr.io/k8s-artifacts-prod/build-image/kube-cross:v1.13.8-1 as build_k8s_1_17_sample_apiserver
 
 ENV GOPATH /go
@@ -32,7 +33,6 @@ RUN GO111MODULE=on CGO_ENABLED=0 GOOS=linux GOARCH=BASEARCH go get k8s.io/sample
 # we can copy it out from this throw away container image from a standard location
 RUN find /go/bin -name sample-apiserver -exec cp {} / \;
 
-ARG BASEIMAGE
 FROM $BASEIMAGE
 COPY --from=build_k8s_1_17_sample_apiserver /sample-apiserver /sample-apiserver