Description
Our acceptance tests for AWS recently failed with a strange false positive. There's a difference on the arn attribute for several resources including:

• aws_vpc
• aws_internet_gateway
• aws_launch_template
• aws_instance

 "differences": [
  {
   "res": {
    "id": "igw-0a32ad37ba06d0545",
    "type": "aws_internet_gateway"
   },
   "changelog": [
    {
     "type": "update",
     "path": [
      "arn"
     ],
     "from": "arn:aws:ec2:us-east-1:994475276861:internet-gateway/igw-0a32ad37ba06d0545",
     "to":     "arn:aws:ec2:us-east-1::internet-gateway/igw-0a32ad37ba06d0545",
     "computed": true
    }
   ]

Investigation must be made in order to identify if it's a bug in driftctl or in the provider itself. As it's a field the user has not control on, we may consider ignoring it. Just like we did for aws_ebs_volume.

It seems to be a bug in provider that computes a wrong value for the arn attribute:

The arn value is computed here, and used here in the provider.

Environment

• OS: linux
• driftctl version: latest
• terraform version: n/a
• terraform providers versions: aws@3.19.0, aws@3.45.0, aws@3.75.2, aws@4.23.0

How to reproduce

Run one of those tests locally:

• TestAcc_Aws_Instance
• TestAcc_Aws_InternetGateway
• TestAcc_Aws_LaunchTemplate
• TestAcc_Aws_VPC

Possible Solution

1. We ignore this attribute just like we did for aws_ebs_volume