tailscale_tailnet_key.description length is not validated - going over the API limit causes permadiff

[grelland]

Describe the bug When setting the description fíeld on tailscale_tailnet_key_ the provider does not do validation on the length, or at least does not validate it according to the API rules, causing a long (above 50) character description to be accepted into the state.

This, in turn, causes a permadiff situation where the resource keeps being recreated (causing a new key to be created) on each apply.

To Reproduce Steps to reproduce the behaviour:

resource "tailscale_tailnet_key" "foobar" {
  expiry          = 123456
  description = "This description is too long and will be cut to 50 chars by the Tailscale API"
}

On initial terraform plan (and then apply):

 # tailscale_tailnet_key.foobar will be created
+ resource "tailscale_tailnet_key" "foobar" {
      + created_at    = (known after apply)
      + description   = "This description is too long and will be cut to 50 chars by the Tailscale API"
      .... snip....
    }

On next run of terraform plan

  # tailscale_tailnet_key.foobar must be replaced
-/+ resource "tailscale_tailnet_key" "foobar" {
      ~ description   = "This description is too long and will be cut to 50" -> "This description is too long and will be cut to 50 chars by the Tailscale API" # forces replacement
      ... snip ...
    }

Expected behaviour The provider should not accept a description which violates the max length and should fail at the plan stage.

Desktop (please complete the following information):

• Terraform Version 1.4.7
• Provider Version 0.13.13