Fix

Author: JamesNK

testassets/InteropTestsGrpcWebWebsite/Tests/custom-environment.js

@@ -1,4 +1,7 @@
 const JestPuppeteerEnvironment = require("jest-environment-puppeteer").TestEnvironment;
+
+// expect-puppeteer requires jest's expect to be on the global object
+global.expect = require('expect').expect;
 const expect = require('expect-puppeteer').expect;
 
 class CustomEnvironment extends JestPuppeteerEnvironment {