call subscribeToOcsApiCallback after the connection to the websocket

src/components/App.js

@@ -75,6 +75,8 @@ function App(){
         const shouldCheckForUpdates = !updateCheckedAt || (updateCheckedAt + updateCheckAfter) < new Date().getTime();
         if (shouldCheckForUpdates) ocsApiState.ocsManagerApi.send('UpdateHandler::checkAll', []);
         setAppInfo();
+      }).then(() => {
+          subscribeToOcsApiCallback();
       });
     }