make run user index update loop when sharding disable

Signed-off-by: SungJin1212 <[email protected]>

Author: SungJin1212

pkg/alertmanager/multitenant.go

@@ -670,7 +670,7 @@ func (am *MultitenantAlertmanager) run(ctx context.Context) error {
 		ringTickerChan = ringTicker.C
 	}
 
-	if am.cfg.ShardingEnabled && am.userIndexUpdater != nil {
+	if am.userIndexUpdater != nil {
 		go am.userIndexUpdateLoop(ctx)
 	}
 

pkg/ruler/ruler.go

@@ -697,7 +697,7 @@ func (r *Ruler) run(ctx context.Context) error {
 		ringTickerChan = ringTicker.C
 	}
 
-	if r.cfg.EnableSharding && r.userIndexUpdater != nil {
+	if r.userIndexUpdater != nil {
 		go r.userIndexUpdateLoop(ctx)
 	}