Activate a service account if this is defined

hack/jenkins/e2e-runner.sh

@@ -151,6 +151,11 @@ if running_in_docker; then
     fi
 fi
 
+if [[ -n "${KUBEKINS_SERVICE_ACCOUNT_FILE:-}" ]]; then
+  echo 'Activating service account...'  # No harm in doing this multiple times.
+  gcloud auth activate-service-account --key-file="${KUBEKINS_SERVICE_ACCOUNT_FILE}"
+fi
+
 # Install gcloud from a custom path if provided. Used to test GKE with gcloud
 # at HEAD, release candidate.
 # TODO: figure out how to avoid installing the cloud sdk twice if run inside Docker.
@@ -345,11 +350,11 @@ if [[ -n "${JENKINS_PUBLISHED_SKEW_VERSION:-}" ]]; then
     if [[ "${JENKINS_USE_SKEW_TESTS:-}" != "true" ]]; then
         # Back out into the old tests now that we've downloaded & maybe upgraded.
         cd ../kubernetes_old
-	# Append kubectl-path of skewed kubectl to test args, since we always
-	# want that to use the skewed kubectl version:
-	#
-	# - for upgrade jobs, we want kubectl to be at the same version as master.
-	# - for client skew tests, we want to use the skewed kubectl (that's what we're testing).
+        # Append kubectl-path of skewed kubectl to test args, since we always
+        # want that to use the skewed kubectl version:
+        #
+        # - for upgrade jobs, we want kubectl to be at the same version as master.
+        # - for client skew tests, we want to use the skewed kubectl (that's what we're testing).
         GINKGO_TEST_ARGS="${GINKGO_TEST_ARGS:-} --kubectl-path=$(pwd)/../kubernetes/cluster/kubectl.sh"
     fi
 fi