code: public CMAApiKey addEnvironment(String environment) {
      environments.add(
          new CMALink(CMAType.Environment).setId(environment)
      );
      return this;
    }
docs: Add environment ids to the api key.
  <p>
  
  @param environment a new environment to be affected by this key.
  A link for the payload will be created automatically.
  @return the api key for easy chaining.