Enable kube-addon-manager leader election

Change-Id: Ica7ffeea7e53857b27fa1ec554713bd2bcbc96f0
Related-PROD: PROD-21703
diff --git a/kubernetes/files/kube-addon-manager/kube-addons.config b/kubernetes/files/kube-addon-manager/kube-addons.config
index c98d034..6c2aefe 100644
--- a/kubernetes/files/kube-addon-manager/kube-addons.config
+++ b/kubernetes/files/kube-addon-manager/kube-addons.config
@@ -1,3 +1,4 @@
 KUBECTL_BIN=/usr/bin/kubectl
 ADDON_PATH=/etc/kubernetes/addons
 TEST_ADDON_CHECK_INTERVAL_SEC=30
+ADDON_MANAGER_LEADER_ELECTION=true