Create a loop that will fire a pillar refresh to inform a master about a change in the grains of this minion
        :param refresh_interval_in_minutes:
        :return: None

def _refresh_grains_watcher(self, refresh_interval_in_minutes):
        '''
        Create a loop that will fire a pillar refresh to inform a master about a change in the grains of this minion
        :param refresh_interval_in_minutes:
        :return: None
        '''
        if '__update_grains' not in self.opts.get('schedule', {}):
            if 'schedule' not in self.opts:
                self.opts['schedule'] = {}
            self.opts['schedule'].update({
                '__update_grains':
                    {
                        'function': 'event.fire',
                        'args': [{}, 'grains_refresh'],
                        'minutes': refresh_interval_in_minutes
                    }
            })