retry should readd to queue

[donyhuang]

https://github.com/apache/apisix-ingress-controller/blob/4b089a3e06af9dd451628c2e41d9ae537101f9ce/pkg/providers/apisix/apisix_plugin_config.go#L287

func (c *apisixPluginConfigController) handleSyncErr(obj interface{}, errOrigin error) {
	if errOrigin == nil {
		c.workqueue.Forget(obj)
		c.MetricsCollector.IncrSyncOperation("PluginConfig", "success")
		return
	}
	ev := obj.(*types.Event)
	if k8serrors.IsNotFound(errOrigin) && ev.Type != types.EventDelete {
		log.Infow("sync ApisixPluginConfig but not found, ignore",
			zap.String("event_type", ev.Type.String()),
			zap.String("ApisixPluginConfig", ev.Object.(kube.ApisixPluginConfigEvent).Key),
		)
		c.workqueue.Forget(obj)
		return
	}
	log.Warnw("sync ApisixPluginConfig failed, will retry",
		zap.Any("object", obj),
		zap.Error(errOrigin),
	)
	c.workqueue.Forget(obj) //is bug should replace with c.workqueue.AddRateLimited(obj)
	c.MetricsCollector.IncrSyncOperation("PluginConfig", "failure")
}