web-ui: Add test command to travis file

Add ChromeHeadlessCI as custom launcher in karma config file

.travis.yml

@@ -23,4 +23,4 @@ matrix:
       - npm install -g @angular-devkit/build-angular
       - npm install
       script:
-      - ng build --prod
+      - npm run test -- --no-watch --no-progress --browsers=ChromeHeadlessCI

web-ui/karma.conf.js

@@ -27,6 +27,12 @@ module.exports = function (config) {
     logLevel: config.LOG_INFO,
     autoWatch: true,
     browsers: ['Chrome'],
+    customLaunchers: {
+      ChromeHeadlessCI: {
+        base: 'ChromeHeadless',
+        flags: ['--no-sandbox', '--disable-gpu']
+      }
+    },
     singleRun: false
   });
 };