Insufficient fastly_tls_subscription validation (400 Bad Request "Must provide TLS configuration relationship")

[nightpool]

Terraform Version

% terraform -v
Terraform v1.10.2
on darwin_arm64

Affected Fastly Terraform Resource(s)

Please list the affected resources, for example:

• fastly_tls_subscription

Terraform Configuration Files

resource "fastly_tls_subscription" "tls" {
  domains               = nonsensitive(var.service.domain[*].name)
  certificate_authority = "lets-encrypt"
}

Expected Behavior

I should have been aware at the planning stage that the resource required a configuration_id.

Actual Behavior

configuration_id was marked as optional, so there was no way for me to tell that it was required by the API

https://gist.github.com/nightpool/98410f3fcfe4cc27d0c0f5fd8441846a

Steps to Reproduce

Please list the steps required to reproduce the issue, for example:

1. terraform apply

Important Factoids (optional)

It does not appear that we have a default TLS config set for our account:

% fastly tls-config list                                                         
NAME          ID                      BULK  DEFAULT  TLS PROTOCOLS  HTTP PROTOCOLS   DNS RECORDS
<redacted>    CbByLy3Rad5QJge6H7fKKA  false  false     1.0, 1.1, 1.2   http/1.1, http/2  
<redacted>    SHcxcEMSAPhBvrgIrAe3uA  false  false     1.2             http/1.1, http/2  

The provider should be able to detect this and enforce a TLS configuration at plan time.