fix test

Author: lforst

packages/nextjs/test/performance/appRouterInstrumentation.test.ts

@@ -1,4 +1,4 @@
-import { WINDOW } from '@sentry/react';
+import { WINDOW, addEventProcessor } from '@sentry/react';
 import type { Client, HandlerDataFetch } from '@sentry/types';
 import * as sentryUtils from '@sentry/utils';
 import { JSDOM } from 'jsdom';
@@ -36,6 +36,7 @@ describe('appRouterInstrumentPageLoad', () => {
     const emit = jest.fn();
     const client = {
       emit,
+      addEventProcessor: jest.fn(),
     } as unknown as Client;
 
     appRouterInstrumentPageLoad(client);