Ignore changes to node count because auto scaling.

main.tf

@@ -199,6 +199,12 @@ resource "google_container_node_pool" "primary" {
     }
   }
 
+  lifecycle {
+    ignore_changes = [
+      node_count
+    ]
+  }
+
   depends_on = [
     google_project_service.container
   ]