Replace app.js with webpack-dev-server (#5797)

e2e/tests/framework/baseFixtures.e2e.spec.js

@@ -23,7 +23,7 @@
 /*
 This test suite is dedicated to testing our use of the playwright framework as it
 relates to how we've extended it (i.e. ./e2e/baseFixtures.js) and assumptions made in our dev environment
-(app.js and ./e2e/webpack-dev-middleware.js)
+(`npm start` and ./e2e/webpack-dev-middleware.js)
 */
 
 const { test } = require('../../baseFixtures.js');