Client VPN Cloudformation Security Groups

Question

I am creating a client vpn in Cloudformation so that my entire VPC setup is contained in a template to duplicate environments. When I have gone to put the client VPN endpoint in I see no way in CloudFormation to associate security groups to my endpoint, which you can do via the console:

There does not seem to by any way to do this, in any one of the following resource types:

• AWS::EC2::ClientVpnEndpoint
• AWS::EC2::ClientVpnTargetNetworkAssociation
• AWS::EC2::ClientVpnAuthorizationRule

It would really be beneficial if I had a way to do this, I don't want to write a custom resource with a Lambda but that's the only way it currently looks like will work without a resource to use.