rules/recording.go
func (rule *RecordingRule) SetEvaluationTimestamp(ts time.Time) {
	rule.mtx.Lock()
	defer rule.mtx.Unlock()
	rule.evaluationTimestamp = ts
}
func (rule *RecordingRule) SetEvaluationTimestamp(ts time.Time) {
	rule.mtx.Lock()
	defer rule.mtx.Unlock()
	rule.evaluationTimestamp = ts
}
// SetEvaluationTimestamp updates evaluationTimestamp to the timestamp of when the rule was last evaluated.