UpCloud server plan, firewall, load balancer integration (#8758)

* [upcloud] add option to use preconfigured cpu/mem plan

* [upcloud] add option to use firewall rules for API server/SSH access

* [upcloud] add option to use managed load balancer

contrib/terraform/upcloud/modules/kubernetes-cluster/variables.tf

@@ -16,6 +16,7 @@ variable "machines" {
   description = "Cluster machines"
   type = map(object({
     node_type       = string
+    plan            = string
     cpu             = string
     mem             = string
     disk_size       =  number
@@ -29,3 +30,38 @@ variable "machines" {
 variable "ssh_public_keys" {
   type = list(string)
 }
+
+variable "firewall_enabled" {
+  type = bool
+}
+
+variable "master_allowed_remote_ips" {
+  type = list(object({
+    start_address = string
+    end_address   = string
+  }))
+}
+
+variable "k8s_allowed_remote_ips" {
+  type = list(object({
+    start_address = string
+    end_address   = string
+  }))
+}
+
+variable "loadbalancer_enabled" {
+  type = bool
+}
+
+variable "loadbalancer_plan" {
+  type = string
+}
+
+variable "loadbalancers" {
+  description = "Load balancers"
+
+  type = map(object({
+    port            = number
+    backend_servers = list(string)
+  }))
+}