Bump k8s version from 1.6.2 to 1.7.3.

* Bumped k8s image version from 1.6.2 to 1.7.3.

Change-Id: I8c81757b4f8c0d816838dc34e9113d17119f31af
diff --git a/classes/cluster/k8s_aio_calico/kubernetes/compute.yml b/classes/cluster/k8s_aio_calico/kubernetes/compute.yml
index 63f79b9..5559236 100644
--- a/classes/cluster/k8s_aio_calico/kubernetes/compute.yml
+++ b/classes/cluster/k8s_aio_calico/kubernetes/compute.yml
@@ -10,7 +10,7 @@
     kubernetes_calicoctl_image: docker-prod-virtual.docker.mirantis.net/mirantis/projectcalico/calico/ctl:latest
     kubernetes_calico_image: docker-prod-virtual.docker.mirantis.net/mirantis/projectcalico/calico/node:latest
     kubernetes_calico_cni_image: docker-prod-virtual.docker.mirantis.net/mirantis/projectcalico/calico/cni:latest
-    kubernetes_hyperkube_image: docker-prod-virtual.docker.mirantis.net/mirantis/kubernetes/hyperkube-amd64:v1.6.2-2
+    kubernetes_hyperkube_image: docker-prod-virtual.docker.mirantis.net/mirantis/kubernetes/hyperkube-amd64:v1.7.3-1
   docker:
     host:
       pkgs: