rules/manager.go
func (g *Group) GetEvaluationTimestamp() time.Time {
	g.mtx.Lock()
	defer g.mtx.Unlock()
	return g.evaluationTimestamp
}
func (g *Group) GetEvaluationTimestamp() time.Time {
	g.mtx.Lock()
	defer g.mtx.Unlock()
	return g.evaluationTimestamp
}
// GetEvaluationTimestamp returns the time the last evaluation of the rule group took place.