Fix pod oom events cannot be emitted

[fighterhit]

Fix pod oom events cannot be emitted due to regular expression error and lack of kernel-monitor rule whose reason is PodOOMKilling.

node-problem-detector/pkg/systemlogmonitor/log_monitor.go

Lines 190 to 194 in 71bd5f8

	matched := l.buffer.Match(rule.Pattern)
	if len(matched) == 0 {
	continue
	}
	status := l.generateStatus(matched, rule)

node-problem-detector/pkg/systemlogmonitor/log_monitor.go

Lines 204 to 206 in 71bd5f8

	message := generateMessage(logs)
	if rule.Reason == OOMREASON && k8sClient != nil {
	uuid := string(uuidRegx.Find([]byte(message)))

Because this is based on whether the reason is PodOOMKilling, so there has to be such a rule that can both be matched by the uuidRegx regular expression in the code.