fix linter

cmd/crowdsec/output.go

@@ -24,8 +24,10 @@ LOOP:
 		case <-outputsTomb.Dying():
 			log.Infof("Flushing outputs")
 			output.FlushAll()
-			log.Infof("Shuting down output routines")
-			output.Shutdown()
+			log.Debugf("Shuting down output routines")
+			if err := output.Shutdown(); err != nil {
+				log.Errorf("error while in output shutdown: %s", err)
+			}
 			log.Infof("Done shutdown down output")
 			break LOOP
 		case event := <-overflow: