fix(vm): `cpu.architecture` showed as new attribute at re-apply after creation

[bpg]

Contributor's Note

• [ ] I have added / updated documentation in /docs for any user-facing features or additions.
• [ ] I have added / updated acceptance tests in /fwprovider/tests for any new or updated resources / data sources.
• [x] I have ran make example to verify that the change works as expected.

Proof of Work

With this template

resource "proxmox_virtual_environment_vm" "test_cdrom" {
  node_name = "pve"
  vm_id     = 999
  started   = false
  name      = "test-cpu-arch"

  cpu {
    cores = 2
    sockets = 1
  }
}

Before the fix:

❯ tofu apply -auto-approve

OpenTofu used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  + create

OpenTofu will perform the following actions:

  # proxmox_virtual_environment_vm.test_cdrom will be created
  + resource "proxmox_virtual_environment_vm" "test_cdrom" {
      + acpi                    = true
      + bios                    = "seabios"
      + id                      = (known after apply)
      + ipv4_addresses          = (known after apply)
      + ipv6_addresses          = (known after apply)
      + keyboard_layout         = "en-us"
      + mac_addresses           = (known after apply)
      + migrate                 = false
      + name                    = "test-cpu-arch"
      + network_interface_names = (known after apply)
      + node_name               = "pve"
      + on_boot                 = true
      + protection              = false
      + reboot                  = false
      + scsi_hardware           = "virtio-scsi-pci"
      + started                 = false
      + stop_on_destroy         = false
      + tablet_device           = true
      + template                = false
      + timeout_clone           = 1800
      + timeout_create          = 1800
      + timeout_migrate         = 1800
      + timeout_move_disk       = 1800
      + timeout_reboot          = 1800
      + timeout_shutdown_vm     = 1800
      + timeout_start_vm        = 1800
      + timeout_stop_vm         = 300
      + vm_id                   = 999

      + cpu {
          + architecture = "x86_64"
          + cores        = 2
          + hotplugged   = 0
          + limit        = 0
          + numa         = false
          + sockets      = 1
          + type         = "qemu64"
          + units        = 1024
        }
    }

Plan: 1 to add, 0 to change, 0 to destroy.
proxmox_virtual_environment_vm.test_cdrom: Creating...
proxmox_virtual_environment_vm.test_cdrom: Creation complete after 1s [id=999]

Apply complete! Resources: 1 added, 0 changed, 0 destroyed.
❯ tofu apply -auto-approve
proxmox_virtual_environment_vm.test_cdrom: Refreshing state... [id=999]

OpenTofu used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  ~ update in-place

OpenTofu will perform the following actions:

  # proxmox_virtual_environment_vm.test_cdrom will be updated in-place
  ~ resource "proxmox_virtual_environment_vm" "test_cdrom" {
        id                      = "999"
        name                    = "test-cpu-arch"
        tags                    = []
        # (26 unchanged attributes hidden)

      ~ cpu {
          + architecture = "x86_64"
            # (8 unchanged attributes hidden)
        }
    }

Plan: 0 to add, 1 to change, 0 to destroy.
proxmox_virtual_environment_vm.test_cdrom: Modifying... [id=999]
proxmox_virtual_environment_vm.test_cdrom: Modifications complete after 0s [id=999]

Apply complete! Resources: 0 added, 1 changed, 0 destroyed.

After the fix:

❯ tofu apply -auto-approve

OpenTofu used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  + create

OpenTofu will perform the following actions:

  # proxmox_virtual_environment_vm.test_cdrom will be created
  + resource "proxmox_virtual_environment_vm" "test_cdrom" {
      + acpi                    = true
      + bios                    = "seabios"
      + id                      = (known after apply)
      + ipv4_addresses          = (known after apply)
      + ipv6_addresses          = (known after apply)
      + keyboard_layout         = "en-us"
      + mac_addresses           = (known after apply)
      + migrate                 = false
      + name                    = "test-cpu-arch"
      + network_interface_names = (known after apply)
      + node_name               = "pve"
      + on_boot                 = true
      + protection              = false
      + reboot                  = false
      + scsi_hardware           = "virtio-scsi-pci"
      + started                 = false
      + stop_on_destroy         = false
      + tablet_device           = true
      + template                = false
      + timeout_clone           = 1800
      + timeout_create          = 1800
      + timeout_migrate         = 1800
      + timeout_move_disk       = 1800
      + timeout_reboot          = 1800
      + timeout_shutdown_vm     = 1800
      + timeout_start_vm        = 1800
      + timeout_stop_vm         = 300
      + vm_id                   = 999

      + cpu {
          + cores      = 2
          + hotplugged = 0
          + limit      = 0
          + numa       = false
          + sockets    = 1
          + type       = "qemu64"
          + units      = 1024
        }
    }

Plan: 1 to add, 0 to change, 0 to destroy.
proxmox_virtual_environment_vm.test_cdrom: Creating...
proxmox_virtual_environment_vm.test_cdrom: Creation complete after 1s [id=999]

Apply complete! Resources: 1 added, 0 changed, 0 destroyed.
❯ tofu apply -auto-approve
proxmox_virtual_environment_vm.test_cdrom: Refreshing state... [id=999]

No changes. Your infrastructure matches the configuration.

OpenTofu has compared your real infrastructure against your configuration and found no differences, so no changes are needed.

Apply complete! Resources: 0 added, 0 changed, 0 destroyed.

Community Note

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Relates: https://github.com/bpg/terraform-provider-proxmox/issues/1494#issuecomment-2336493597