Fix documentation of owned-by option in groups REST API

Bug: Issue 12698
Change-Id: Ia3b75b11cab70100f927d3237f4792a8807f7be9
diff --git a/Documentation/rest-api-groups.txt b/Documentation/rest-api-groups.txt
index 00fd81f..85f7329 100644
--- a/Documentation/rest-api-groups.txt
+++ b/Documentation/rest-api-groups.txt
@@ -126,13 +126,13 @@
 
 ==== Find groups that are owned by another group
 
-By setting `ownedBy` and specifying the link:#group-id[\{group-id\}] of another
+By setting `owned-by` and specifying the link:#group-id[\{group-id\}] of another
 group, it is possible to find all the groups for which the owning group is the
 given group.
 
 .Request
 ----
-  GET /groups/?ownedBy=7ca042f4d5847936fcb90ca91057673157fd06fc HTTP/1.0
+  GET /groups/?owned-by=7ca042f4d5847936fcb90ca91057673157fd06fc HTTP/1.0
 ----
 
 .Response