Telemetry: Record when a mount succesfully starts

Author: jeschu1

GVFS/GVFS.Mount/InProcessMount.cs

@@ -141,7 +141,8 @@ public void Mount(EventLevel verbosity, Keywords keywords)
                         // Use TracingConstants.MessageKey.InfoMessage rather than TracingConstants.MessageKey.CriticalMessage
                         // as this message should not appear as an error
                         { TracingConstants.MessageKey.InfoMessage, "Virtual repo is ready" },
-                    });
+                    },
+                    Keywords.Telemetry);
 
                 this.currentState = MountState.Ready;