Add support for Linode Interfaces

[zliang-akamai]

Merge from project branch to dev. This is basically same as #337, which has been reviewed and approved

Testing

go test ./builder/linode -run TestBuilderPrepare_LinodeNetworkInterfaces

locals { timestamp = regex_replace(timestamp(), "[- TZ:]", "") }

source "linode" "example" {
  image             = "linode/ubuntu24.04"
  image_description = "My Private Image"
  image_label       = "private-image-${local.timestamp}"
  instance_label    = "temporary-linode-${local.timestamp}"
  instance_type     = "g6-standard-1"
  region            = "us-mia"
  ssh_username      = "root"
  interface_generation = "linode"

  linode_interface {
    firewall_id = 2930969 // this firewall must allow SSH from your IP otherwise Packer won't be able to connect to it
    public {
    }
  }
}

build {
  sources = ["source.linode.example"]
}