test(e2e): Port the React Router lazy routes E2E app to span streaming

Removes the `traceLifecycle: 'static'` pin from `react-router-7-lazy-routes`
and rewrites its specs against streamed span v2.

The span-leaking and GQL attribution specs group streamed spans by trace
instead of reading a transaction's `spans` array, and they match fetch spans on
`url.full`, since a streamed `http.client` span carries only the domain in its
name.

Author: andreiborza

dev-packages/e2e-tests/test-applications/react-router-7-lazy-routes/src/index.tsx

@@ -78,7 +78,6 @@ const lazyRouteManifest = [
 ];
 
 Sentry.init({
-  traceLifecycle: 'static',
   environment: 'qa', // dynamic sampling bias to keep transactions
   dsn: process.env.REACT_APP_E2E_TEST_DSN,
   integrations: [