Update Kubernetes from v1.17.3 to v1.17.4

* https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.17.md#v1174

google-cloud/container-linux/kubernetes/README.md

@@ -11,7 +11,7 @@ Typhoon distributes upstream Kubernetes, architectural conventions, and cluster
 
 ## Features <a href="https://www.cncf.io/certification/software-conformance/"><img align="right" src="https://storage.googleapis.com/poseidon/certified-kubernetes.png"></a>
 
-* Kubernetes v1.17.3 (upstream)
+* Kubernetes v1.17.4 (upstream)
 * Single or multi-master, [Calico](https://www.projectcalico.org/) or [flannel](https://github.com/coreos/flannel) networking
 * On-cluster etcd with TLS, [RBAC](https://kubernetes.io/docs/admin/authorization/rbac/)-enabled, [network policy](https://kubernetes.io/docs/concepts/services-networking/network-policies/)
 * Advanced features like [worker pools](https://typhoon.psdn.io/advanced/worker-pools/), [preemptible](https://typhoon.psdn.io/cl/google-cloud/#preemption) workers, and [snippets](https://typhoon.psdn.io/advanced/customization/#container-linux) customization

google-cloud/container-linux/kubernetes/bootstrap.tf

@@ -1,6 +1,6 @@
 # Kubernetes assets (kubeconfig, manifests)
 module "bootstrap" {
-  source = "git::https://github.com/poseidon/terraform-render-bootstrap.git?ref=804029edd5a6a5cf02e0db4919e7f2bb601d0089"
+  source = "git::https://github.com/poseidon/terraform-render-bootstrap.git?ref=73784c1b2c791d9ba586a1478979ac34dd324dad"
 
   cluster_name          = var.cluster_name
   api_servers           = [format("%s.%s", var.cluster_name, var.dns_zone)]

google-cloud/container-linux/kubernetes/cl/controller.yaml

@@ -90,7 +90,7 @@ systemd:
           --mount volume=var-log,target=/var/log \
           --volume opt-cni-bin,kind=host,source=/opt/cni/bin \
           --mount volume=opt-cni-bin,target=/opt/cni/bin \
-          docker://k8s.gcr.io/hyperkube:v1.17.3 \
+          docker://k8s.gcr.io/hyperkube:v1.17.4 \
           --exec=/usr/local/bin/kubelet -- \
           --anonymous-auth=false \
           --authentication-token-webhook \
@@ -134,7 +134,7 @@ systemd:
             --volume script,kind=host,source=/opt/bootstrap/apply \
             --mount volume=script,target=/apply \
             --insecure-options=image \
-            docker://k8s.gcr.io/hyperkube:v1.17.3 \
+            docker://k8s.gcr.io/hyperkube:v1.17.4 \
             --net=host \
             --dns=host \
             --exec=/apply

google-cloud/container-linux/kubernetes/workers/cl/worker.yaml

@@ -63,7 +63,7 @@ systemd:
           --mount volume=var-log,target=/var/log \
           --volume opt-cni-bin,kind=host,source=/opt/cni/bin \
           --mount volume=opt-cni-bin,target=/opt/cni/bin \
-          docker://k8s.gcr.io/hyperkube:v1.17.3 \
+          docker://k8s.gcr.io/hyperkube:v1.17.4 \
           --exec=/usr/local/bin/kubelet -- \
           --anonymous-auth=false \
           --authentication-token-webhook \
@@ -126,7 +126,7 @@ storage:
             --volume config,kind=host,source=/etc/kubernetes \
             --mount volume=config,target=/etc/kubernetes \
             --insecure-options=image \
-            docker://k8s.gcr.io/hyperkube:v1.17.3 \
+            docker://k8s.gcr.io/hyperkube:v1.17.4 \
             --net=host \
             --dns=host \
             -- \