[AAE-10594] Run unit tests in headless mode (#8141)

* AAE-10594 - changed karma configs to run unit tests in headless mode

* AAE-10594 - removed commets

* [AAE-10594] fixed failing test

lib/testing/karma.conf.js

@@ -24,7 +24,7 @@ module.exports = function (config) {
     colors: true,
     logLevel: config.LOG_INFO,
     autoWatch: true,
-    browsers: ['Chrome'],
+    browsers: ['ChromeHeadless'],
     singleRun: true
   });
 };