fix #1015, call accesscontrol.closeSession when a session times out

src/server/ua_session_manager.c

@@ -61,6 +61,8 @@ UA_SessionManager_cleanupTimedOut(UA_SessionManager *sm,
             continue;
         UA_LOG_INFO_SESSION(sm->server->config.logger, &sentry->session,
                             "Session has timed out");
+        sm->server->config.accessControl.closeSession(&sentry->session.sessionId,
+                                                      sentry->session.sessionHandle);
         removeSession(sm, sentry);
     }
 }