Update instance shapes used in CI tests.

Author: jlamillan

tests/resources/configs/public-cluster.tfvars

@@ -9,8 +9,8 @@ control_plane_subnet_access = "public"
 k8s_master_lb_access = "public"
 master_oci_lb_enabled = "false"
 etcd_lb_enabled = "false"
-etcdShape = "VM.Standard1.8"
-k8sMasterShape = "VM.Standard1.8"
+etcdShape = "VM.Standard2.4"
+k8sMasterShape = "VM.Standard2.8"
 k8sWorkerShape = "BM.DenseIO1.36"
 etcdAd1Count = "1"
 etcdAd2Count = "0"