Unable to find device notification key

Summary: Add a key such that the same notification does not appear again for the same device/app.

Reviewed By: antonk52

Differential Revision: D47835045

fbshipit-source-id: 78237b4102aa199ebea23b7c5726b567fc4de91e

desktop/flipper-ui-core/src/dispatcher/flipperServer.tsx

@@ -308,6 +308,7 @@ export async function handleClientConnected(
           e,
         );
         notification.error({
+          key: `device-find-failure-${query.device_id}`,
           message: 'Connection failed',
           description: `Failed to find device '${query.device_id}' while trying to connect app '${query.app}'`,
           duration: 0,