Unnecessary error is logged when resource usage is increased

	appGroup := userTracker.getGroupForApp(applicationID)
	log.Log(log.SchedUGM).Debug("Increasing resource usage for user",
		zap.String("user", user.User),
		zap.String("queue path", queuePath),
		zap.String("application", applicationID),
		zap.String("group", appGroup),
		zap.Stringer("resource", usage))
	groupTracker := m.GetGroupTracker(appGroup)
	if groupTracker == nil {
		log.Log(log.SchedUGM).Error("group tracker should be available in groupTrackers map",
		zap.String("application", applicationID),
		zap.String("group", appGroup))
		return
	}
...

func (ut *UserTracker) increaseTrackedResource(queuePath string, applicationID string, usage *resources.Resource) {
	ut.Lock()
	defer ut.Unlock()
	ut.events.sendIncResourceUsageForUser(ut.userName, queuePath, usage)
	hierarchy := strings.Split(queuePath, configs.DOT)
	ut.queueTracker.increaseTrackedResource(hierarchy, applicationID, user, usage)
	gt := ut.appGroupTrackers[applicationID]
	log.Log(log.SchedUGM).Debug("Increasing resource usage for group",
		zap.String("group", gt.getName()),
		zap.Strings("queue path", hierarchy),
		zap.String("application", applicationID),
		zap.Stringer("resource", usage))
	gt.increaseTrackedResource(queuePath, applicationID, usage, ut.userName) <- can be null
}