Update Linode resize to differentiate between warm and cold migrations

[ezilber-akamai]

📝 Description

Add a check for migration type before resizing instance to allow for both warm and cold migration types.

✔️ How to Test

The following steps assume you have pulled down and checked out this PR locally.

Integration Testing

make PKG_NAME=linode/instance int-test

NOTE: This test will take a long time to run and may have intermittent failures.

Manual Testing

Run the following TF scripts in a sandbox environment (i.e. dx-devenv).

Cold Migration

1. Create a simple instance

resource "linode_instance" "foobar" {
    label = "test-tf"
    type = "g6-standard-1"
    region = "us-east"
    image = "linode/ubuntu22.04"
    firewall_id = <YOUR FIREWALL ID>
} 

2. Ensure instance is created and running in Cloud Manager.
3. Update the instance to a different type (g6-standard-1 to g6-standard-2). You do not need to specify migration_type, as it defaults to cold.

resource "linode_instance" "foobar" {
    label = "test-tf"
    type = "g6-standard-2"
    region = "us-east"
    image = "linode/ubuntu22.04"
    firewall_id = <YOUR FIREWALL ID>
} 

4. Once the process completes, look at the events in Cloud Manager. Note that the instance was shut down prior to being resized (as is expected for a cold migration). Ensure that the instance is running.
5. Clean up the resources generated in this test.

Warm Migration

1. Create a simple instance

resource "linode_instance" "foobar" {
    label = "test-tf"
    type = "g6-standard-1"
    region = "us-east"
    image = "linode/ubuntu22.04"
    firewall_id = <YOUR FIREWALL ID>
} 

2. Ensure instance is created and running in Cloud Manager.
3. Update the instance to a different type (g6-standard-1 to g6-standard-2). You do need to specify migration_type, as we want it to be warm instead of the default of cold.

resource "linode_instance" "foobar" {
    label = "test-tf"
    type = "g6-standard-2"
    region = "us-east"
    image = "linode/ubuntu22.04"
    firewall_id = <YOUR FIREWALL ID>
    migration_type = "warm"
} 

4. Once the process completes, look at the events in Cloud Manager. Note that the instance was not shut down prior to being resized (as is expected for a warm migration). Ensure that the instance is running.
5. Clean up the resources generated in this test.