test: support -tags cluster_proxy for e2e tests

test

@@ -171,6 +171,7 @@ function cov_pass {
 	# due to many tests cause etcd process to wait
 	# on leadership transfer timeout during gracefully shutdown
 	go test -tags cov -timeout 30m -v ${REPO_PATH}"/e2e" || failed="$failed e2e"
+	go test -tags cov,cluster_proxy -timeout 30m -v ${REPO_PATH}"/e2e" || failed="$failed e2e-proxy"
 
 	# incrementally merge to get coverage data even if some coverage files are corrupted
 	# optimistically assume etcdserver package's coverage file is OK since gocovmerge
@@ -217,6 +218,7 @@ function integration_e2e_pass {
 function grpcproxy_pass {
 	go test -timeout 20m -v ${RACE} -tags cluster_proxy -cpu 1,2,4 $@ ${REPO_PATH}/integration
 	go test -timeout 15m -v ${RACE} -tags cluster_proxy -cpu 1,2,4 $@ ${REPO_PATH}/clientv3/integration
+	go test -timeout 15m -v -tags cluster_proxy $@ ${REPO_PATH}/e2e
 }
 
 function release_pass {