Update Butane Config from v1.2.0 to v1.4.0

* Rename Fedora CoreOS Config (FCC) to Butane Config
* Require any snippets customizations use version v1.4.0

* https://typhoon.psdn.io/advanced/customization/#hosts

bare-metal/fedora-coreos/kubernetes/fcc/controller.yaml

@@ -1,6 +1,6 @@
 ---
 variant: fcos
-version: 1.2.0
+version: 1.4.0
 systemd:
   units:
     - name: etcd-member.service

bare-metal/fedora-coreos/kubernetes/fcc/worker.yaml

@@ -1,6 +1,6 @@
 ---
 variant: fcos
-version: 1.2.0
+version: 1.4.0
 systemd:
   units:
     - name: docker.service

bare-metal/fedora-coreos/kubernetes/variables.tf

@@ -57,7 +57,7 @@ EOD
 
 variable "snippets" {
   type        = map(list(string))
-  description = "Map from machine names to lists of Fedora CoreOS Config snippets"
+  description = "Map from machine names to lists of Butane snippets"
   default     = {}
 }