Undefined *_common_name --> fail to create Client VPN

[bfejervari-nitro]

Describe the Bug

I tried to use the module without minimal (mainly the required inputs) configuration and got the following error:

* Failed to execute "tofu apply" in ./.terragrunt-cache/rlzfG_8xq-XM7mH3sc0jHKuR6E0/kGAWRK4NH1tKgat2ftMVayOrG3A
  ╷
  │ Error: creating EC2 Client VPN Endpoint: operation error EC2: CreateClientVpnEndpoint, https response error StatusCode: 400, RequestID: a7c5eae0-f03a-49f7-97ae-e882f822542a, api error InvalidParameterValue: Certificate arn:aws:acm:eu-central-1:523327511767:certificate/d90babbe-6faf-4778-b6ee-a8d731da5ea9 does not have a domain
  │
  │   with aws_ec2_client_vpn_endpoint.default[0],
  │   on main.tf line 154, in resource "aws_ec2_client_vpn_endpoint" "default":
  │  154: resource "aws_ec2_client_vpn_endpoint" "default" {
  │
  ╵

Investigating the cause of the problem showed that the self signed certificate was created without a domain name. I've attached a screenshot.

Workaround 1
Setting name input to a string can solve the problem.

name      = "testtesttest"

Workaround 2
Setting *_common_name inputs to a domain name like string solved the problem. Setting a simple word (not containing . characters) didn't help.

ca_common_name          = "vpn-ca-cert.vpn.mydomain"
root_common_name        = "vpn-root-cert.vpn.mydomain"
server_common_name      = "vpn-server-cert.vpn.mydomain"

Suggested solution
Please make it clear that one of the following inputs must be defined:

• name (as this is used e.g. in exporting full_client_configuration, this should be marked as Required)
• all _common_name certificate fields (using domain-name string)

Expected Behavior

Without setting optional inputs, everything goes well, Client VPN endpoint is created.
Or it's made clear that among the optional inputs, there are some group(s) which are required.

Steps to Reproduce

• Terragrunt project
• create VPC
• create AWS Client VPN endpoint by using following configuration:

  dependency "vpc" {
    config_path = "${get_terragrunt_dir()}/../vpc"
  }
  
  terraform {
    source = "tfr:///cloudposse/ec2-client-vpn/aws?version=1.1.0"
  }
  
  inputs = {
    vpc_id                  = dependency.vpc.outputs.vpc_id
    associated_subnets      = dependency.vpc.outputs.private_subnets
    client_cidr             = "10.0.0.0/16"
    logging_enabled         = false
    logging_stream_name     = "client-vpn"
    organization_name       = "test-project"
  }

Screenshots

Environment

No response

Additional Context

No response