Update connection.html.markdown

Fixed the Connections JSON example to remove an erroneous comma.

Author: kevin-sumo

website/docs/r/connection.html.markdown

@@ -38,7 +38,7 @@ JSON
   "client" : "Sumo Logic",
   "eventType" : "{{Name}}",
   "description" : "{{Description}}",
-  "search_url" : "{{QueryUrl}}",
+  "search_url" : "{{QueryUrl}}"
 }
 JSON
   webhook_type    = "Webhook"