Add helm-operator query example

docs/maintenance.md

@@ -26,12 +26,17 @@ Please also refer to the [LogQL documentation](https://github.com/grafana/loki/b
 
 #### Flux
 
-Flux is responsible for installing applications. 
+Flux is responsible for installing applications. It used `helm-operator` to
+deploy the desired helm releases.
 
 Query all messages from `flux`:
 
     {app="flux"}
 
+Query all messages from `flux` and `helm-operator`:
+
+    {app=~"(flux|helm-operator)"}
+
 `flux` messages containing `wordpress`:
 
     {app = "flux"} |= "wordpress"