Enable CI on drone (#6)

src/karma.conf.js

@@ -1,13 +1,16 @@
 // Karma configuration file, see link for more information
 // https://karma-runner.github.io/1.0/config/configuration-file.html
 
+process.env.CHROME_BIN = require('puppeteer').executablePath();
+
 module.exports = function (config) {
   config.set({
     basePath: '',
     frameworks: ['jasmine', '@angular-devkit/build-angular'],
     plugins: [
-      require('karma-jasmine'),
       require('karma-chrome-launcher'),
+      require('karma-jasmine'),
+      require('karma-nightmare'),
       require('karma-jasmine-html-reporter'),
       require('karma-coverage-istanbul-reporter'),
       require('@angular-devkit/build-angular/plugins/karma')
@@ -25,7 +28,13 @@ module.exports = function (config) {
     colors: true,
     logLevel: config.LOG_INFO,
     autoWatch: true,
-    browsers: ['Chrome'],
+    browsers: ['ChromeHeadless'],
+    customLaunchers: {
+      ChromeHeadlessNoSandbox: {
+        base: 'ChromeHeadless',
+        flags: ['--no-sandbox']
+      }
+    },
     singleRun: false
   });
 };