Remove deprecated `tls-ca-file` option from kube-apiserver

tls-ca-file flag is unused and was removed from kube-apiserver
in kubernetes 1.11. This means that any cluster with this
option specified will fail on apiserver start
Pull request on flag removal:
https://github.com/kubernetes/kubernetes/pull/61386

Task: 24858
Story: 2003566

Change-Id: I9c192b94056629a949ee92d867e8cda5c4ff6810

magnum/drivers/common/templates/kubernetes/fragments/configure-kubernetes-master.sh

@@ -71,7 +71,6 @@ else
     KUBE_API_ARGS="$KUBE_API_ARGS --authorization-mode=Node,RBAC --tls-cert-file=$CERT_DIR/server.crt"
     KUBE_API_ARGS="$KUBE_API_ARGS --tls-private-key-file=$CERT_DIR/server.key"
     KUBE_API_ARGS="$KUBE_API_ARGS --client-ca-file=$CERT_DIR/ca.crt"
-    KUBE_API_ARGS="$KUBE_API_ARGS --tls-ca-file=${CERT_DIR}/ca.crt"
     KUBE_API_ARGS="$KUBE_API_ARGS --service-account-key-file=${CERT_DIR}/service_account.key"
     KUBE_API_ARGS="$KUBE_API_ARGS --kubelet-certificate-authority=${CERT_DIR}/ca.crt --kubelet-client-certificate=${CERT_DIR}/server.crt --kubelet-client-key=${CERT_DIR}/server.key --kubelet-https=true"
 fi