OCPBUGS-33709: GCP mixup when using the ignition shim vs the signed url

** Ignition was being given the signed url, but the url does not point to ignition data
that contains the proxy information. The ignition shim contains the url and should be supplied
as metadata to the bootstrap node. The shim will contain the url as well as proxy data, and the url
will point to the bucket that contains the actual ignition bootstrap data.

Author: barbacbd

data/data/gcp/bootstrap/main.tf

@@ -118,7 +118,7 @@ resource "google_compute_instance" "bootstrap" {
   }
 
   metadata = {
-    user-data = data.ignition_config.redirect.rendered
+    user-data = var.gcp_ignition_shim
   }
 
   tags = ["${var.cluster_id}-master", "${var.cluster_id}-bootstrap"]