Move all E2E dependencies into its own folder, run from there (#3068)

* Move all E2E dependencies into its own folder, run from there

* Run flaky-tests from E2E folder

* This should work better

* Fix E2E test for Linux

* Fix for Windows, fix lint

e2e/webpack.config.performance.js

@@ -0,0 +1,13 @@
+// Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+const glob = require('glob');
+const {merge} = require('webpack-merge');
+
+const test = require('./webpack.config.test');
+
+module.exports = merge(test, {
+    entry: {
+        e2e: glob.sync('./e2e/performance/**/*.test.js'),
+    },
+});