skymarshal: behaviour: Handle groups as maps

There are cases when groups are represented as a list
of maps, not strings e.g. "groups":[{"id":"1",
"name":"gr1"},{"id": "2", "name":"gr2"}]. Handle groups
represented as a list of maps.

concourse/dex#23

Signed-off-by: Vlad Safronov <vladislav.safronov@oracle.com>

connector/oauth/oauth.go

@@ -247,6 +247,9 @@ func (c *oauthConnector) addGroupsFromMap(groups map[string]struct{}, result map
 		if groupString, ok := group.(string); ok {
 			groups[groupString] = struct{}{}
 		}
+		if groupMap, ok := group.(map[string]interface{}); ok {
+			groups[groupMap["name"]] = true
+		}
 	}
 
 	return nil