test: Add package.json script for running Karma tests locally using Chrome (#651)

## Summary

Make it easy to run the Karma tests locally, not via Browserstack.

## Test plan

Run tests

Author: mjc1283

packages/optimizely-sdk/CHANGELOG.MD

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+### Changed
+- Add package.json script for running Karma tests locally using Chrome ([#651](https://github.com/optimizely/javascript-sdk/pull/651)).
+
 ## [4.9.1] - January 18, 2022
 
 ### Bug fixes

packages/optimizely-sdk/karma.local_chrome.bs.conf.js

@@ -0,0 +1,29 @@
+/**
+ * Copyright 2021 Optimizely
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+const baseConfig = require('./karma.base.conf');
+
+module.exports = function(config) {
+  config.set({
+    ...baseConfig,
+    plugins: ['karma-mocha', 'karma-webpack', 'karma-chrome-launcher'],
+    browserStack: null,
+    browsers: ['Chrome'],
+    files: [
+      './node_modules/promise-polyfill/dist/polyfill.min.js',
+      './lib/index.browser.tests.js'
+    ],
+  });
+}

packages/optimizely-sdk/karma.local_chrome.umd.conf.js

@@ -0,0 +1,30 @@
+/**
+ * Copyright 2021 Optimizely
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+const baseConfig = require('./karma.base.conf');
+
+module.exports = function(config) {
+  config.set({
+    ...baseConfig,
+    plugins: ['karma-mocha', 'karma-webpack', 'karma-chrome-launcher'],
+    browserStack: null,
+    browsers: ['Chrome'],
+    files: [
+      './node_modules/promise-polyfill/dist/polyfill.min.js',
+      './dist/optimizely.browser.umd.min.js',
+      './lib/index.browser.umdtests.js'
+    ],
+  });
+}

packages/optimizely-sdk/package.json

@@ -15,6 +15,7 @@
     "test-ci": "npm run test-xbrowser && npm run test-umdbrowser",
     "test-xbrowser": "karma start karma.bs.conf.js --single-run",
     "test-umdbrowser": "npm run build-browser-umd && karma start karma.umd.conf.js --single-run",
+    "test-karma-local": "karma start karma.local_chrome.bs.conf.js && npm run build-browser-umd && karma start karma.local_chrome.umd.conf.js",
     "prebuild": "npm run clean",
     "build": "rollup -c",
     "build-browser-umd": "rollup -c --config-umd",