update k8s as in SEBA-559, upstream apt repo broken

Change-Id: Ib2968f7679b9bcd281463068e098d205e3297220
diff --git a/packer/provision/basebuild.sh b/packer/provision/basebuild.sh
index abfb6ee..7a3bab7 100644
--- a/packer/provision/basebuild.sh
+++ b/packer/provision/basebuild.sh
@@ -112,9 +112,9 @@
         httpie \
         jq \
         kafkacat \
-        "kubeadm=1.12.4-*" \
-        "kubelet=1.12.4-*" \
-        "kubectl=1.12.4-*" \
+        "kubeadm=1.12.7-*" \
+        "kubelet=1.12.7-*" \
+        "kubectl=1.12.7-*" \
         less \
         libmysqlclient-dev \
         libpcap-dev \