doc fix example

doc/example.md

@@ -42,7 +42,7 @@ You can check first that indexer is on the same network as Duniter node:
 
 ```sh
 # check if indexer is on the same chain as duniter
-gcli check-indexer-against-blockchain
+gcli indexer check
 ```
 
 The following commands uniquely relate with indexer.