packer build fails when a template name is provided for the source_template option

Documentation for the source_template option in the cloudstack source block at https://developer.hashicorp.com/packer/plugins/builders/cloudstack says that "the **name** or ID of the template used as base template for the instance" is allowed. When using the name of the template, packer returns this error:

Error retrieving UUID of template : No match found for : &{Count:0 Templates:[]}

Only the ID of a template appears to be accepted. Need to be able to specify template name as well.