Failure to create combined chain but not the chain

[Lasering]

Cookbook Version

2.1.0

Chef Client Version

13.8.5

Scenario

I want to create a certificate, its key and a combined chain from an encrypted data bag, but not the chain.

Steps to Reproduce

ssl_certificate 'vault-server' do
  source 'data-bag'
  bag 'a-data-bag'
  item 'a-data-bag-item'

  chain_name nil
  chain_combined_name 'vault-server.bundle.pem'
  
  cert_item_key 'vault-server-cert'
  key_item_key 'vault-server-key'
  chain_item_key 'vault-server-chain'
  
  encrypted true
  secret_file Chef::Config[:encrypted_data_bag_secret]
  
  key_mode '0640'
end

The data bag item contains all the item keys and the key vault-server-chain contains the certificates of the CAs (intermediate and root).

Expected Result

The file vault-server.bundle.pem should have as content the certificate followed by the chain.

Actual Result

The file vault-server.bundle.pem only contains just the certificate.
However if I set chain_name (eg: to vault-server.chain.pem) then the combined chain is correctly created.

This issue is very similar to #38 the difference is that the chain_combined is expecting the chain file to exist.