docs: def _validate_required(self, settings, name, value):
          """
          Validate a required setting (value can not be empty)
  
          Args:
              settings (dict): Current settings.
              name (str): Setting name.
              value (str): Required value to validate.
  
          Raises:
              boussole.exceptions.SettingsInvalidError: If value is empty.
  
          Returns:
              str: Validated value.
  
          """
          if not value:
              raise SettingsInvalidError(("Required value from setting '{name}' "
                                          "must not be "
                                          "empty.").format(name=name))
  
          return value