Using APIOPS how to add named values into policies.xml

Question

I'm now working with https://github.com/Azure/apiops on a project to interact with an APIM resource. This means any API that I need to work on goes through the apiops repository. We have file(s) configuration.<env>.yaml That contains something like:

apimServiceName: nameofapimresource
namedValues:
  - name: azureTenantNameId
    properties:
      value: "xxx"
  - name: azureEnvironmentId
    properties:
      value: "dev"

From the documentation, those variables are supposed to work and resolve using brackets. ex: {{azureTenantNameId}} Still, if I apply it to a policy.xml it's not translated into any value.

How are we supposed to work with variables in apiops?

Btw, those variables work using brackets on a Specifications.json file