async loadDefaultValues() {
    const parameters = this.templateConfig.parameters;
    const defaultValues = Object.keys(parameters || {}).filter(key => parameters[key].default);

    defaultValues.filter(dv => this.templateParams[dv] === undefined).forEach(dv =>
      Object.defineProperty(this.templateParams, dv, {
        enumerable: true,
        get() {
          return parameters[dv].default;
        }
      })
    );
  }
Loads default values of parameters from template config. If value was already set as parameter it will not be
overriden.
@private