try to add root device name for ami

hosts/arrow/aws/ec2.tf

@@ -3,9 +3,9 @@ resource "aws_instance" "instance" {
   instance_type          = var.ec2_size
   vpc_security_group_ids = [aws_security_group.instance.id]
 
-  tags = merge(local.default_tags, {
+  tags = {
     Name = "aws-nixos"
-  })
+  }
 
   lifecycle {
     create_before_destroy = true

hosts/arrow/aws/image.tf

@@ -71,6 +71,7 @@ resource "aws_ami" "image" {
   description         = "Created with NixOS."
   name                = replace(basename(local.image_file), "/\\.vhd$/", "")
   virtualization_type = "hvm"
+  root_device_name    = "/dev/xvda"
 
   ebs_block_device {
     device_name = "/dev/xvda"