ssh-host-fingerprints causes unexpected diff when specifying user data for instance

[ndrpnt]

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Terraform Version

terraform -v      
Terraform v1.5.7
on darwin_amd64
+ provider registry.terraform.io/scaleway/scaleway v2.47.0

Affected Resource(s)

• scaleway_instance_server

Terraform Configuration Files

resource "scaleway_instance_ip" "example" {}

resource "scaleway_instance_server" "example" {
  name   = "example"
  type   = "PLAY2-PICO"
  image  = "ubuntu_noble"
  ip_ids = [scaleway_instance_ip.example.id]

  user_data = {
    foo = "bar"
  }
}

Expected Behavior

• First terraform apply: Apply complete! Resources: 2 added, 0 changed, 0 destroyed.
• Second terraform apply: No changes. Your infrastructure matches the configuration.

Actual Behavior

• First terraform apply: Apply complete! Resources: 2 added, 0 changed, 0 destroyed.
• Second terraform apply:

  Terraform will perform the following actions:
  
  # scaleway_instance_server.example will be updated in-place
  ~ resource "scaleway_instance_server" "example" {
        id                     = "fr-par-1/8ddc7dda-5900-4888-88e7-45954858df23"
        name                   = "example"
      ~ user_data              = {
          - "ssh-host-fingerprints" = <<-EOT
                256 SHA256:Ar8UZbObn5a50JNVFRv9a3+UTaikTsuDRhhcwmhYGiU root@example (ED25519)
                256 SHA256:2wt5gLFSgsfaBVPPjPa4oJKjeC08xXEDt3Dg1Gg3IxY root@example (ECDSA)
                3072 SHA256:Aczmai9uDBZtZAISLOL1pKjCi+Uduf++18dqoriHEHg root@example (RSA)
            EOT -> null
            # (1 unchanged element hidden)
        }
        # (17 unchanged attributes hidden)
  
        # (2 unchanged blocks hidden)
    }
  
  Plan: 0 to add, 1 to change, 0 to destroy.

Steps to Reproduce

1. terraform apply
2. Wait a few minutes, for the instance to boot I guess ?
3. terraform apply

Important Factoids

Not exactly sure what it takes to reproduce. The diff doesn't always happen and it seems that having a public IP and waiting a few minutes for the instance to boot between 1st and 2nd apply is required.