Update Graphql section in tutorial - concurrency 1
This will make the tutorial work on machines with less than `1GB` of RAM. Addresses
@@ -14,7 +14,7 @@ configuration:
......... address := "127.0.0.1",
......... port := 8888,
......... user := "http",
- ......... concurrency := 4,
+ ......... concurrency := 1,
......... };
CONFIGURE SYSTEM
