Fix Tags; Add Firewall ID, User Data; Other MISC Updates

[zliang-akamai]

📝 Description

Multiple updates bundled:

• Error checking that checks an always-nil err has been removed.
• Many interface{} were replaced with any.
• Add support for firewall_id and user_data of metadata attribute.
• instance_tags and its validation regular expression have been fixed.

Closes #221
Closes #220

✔️ How to Test

Automated Testing

make test

Manual Testing

• Save this in a file called test.pkr.hcl.

source "linode" "example" {
  image             = "linode/ubuntu22.04"
  instance_type     = "g6-nanode-1"
  region            = "us-mia"
  ssh_username      = "root"
  instance_tags     = ["abc", "foo=bar"]
  firewall_id       = 12345 // use your firewall ID here
  metadata {
    user_data = base64encode(<<EOF
#cloud-config

write_files:
  - path: /root/helloworld.txt
    content: |
      Hello, world!
    owner: 'root:root'
    permissions: '0644'
EOF
)
  }
}

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

• go build
• packer build .

[lgarber-akamai]

LGTM, thank you for addressing this!

[yec-akamai]

Great work!