move random_pet to host module

modules/host/main.tf

@@ -1,5 +1,25 @@
+resource "random_pet" "server" {
+  length  = 1
+  keepers = {
+    # We re-create the id (and server) whenever one of those attributes
+    # changes. This should include all input variables to this module,
+    # but NO SENSITIVE values as they might be logged here.
+    name = var.name
+    public_key = var.public_key
+    additional_public_keys = join(",", var.additional_public_keys)
+    ssh_keys = join(",", var.ssh_keys)
+    firewall_ids = join(",", var.firewall_ids)
+    placement_group_id = var.placement_group_id
+    labels = join(",", [for k, v in var.labels: "${k}=${v}" ])
+    location = var.location
+    ipv4_subnet_id = var.ipv4_subnet_id
+    private_ipv4 = var.private_ipv4
+    server_type = var.server_type
+  }
+}
+
 resource "hcloud_server" "server" {
-  name = var.name
+  name = local.name
 
   image              = "ubuntu-20.04"
   rescue             = "linux64"
@@ -90,7 +110,7 @@ data "template_cloudinit_config" "config" {
     content = templatefile(
       "${path.module}/templates/userdata.yaml.tpl",
       {
-        hostname          = var.name
+        hostname          = local.name
         sshAuthorizedKeys = concat([local.ssh_public_key], var.additional_public_keys)
       }
     )