chore(deps): update dependency karma-firefox-launcher to v2

Author: renovate-bot

package.json

@@ -26,7 +26,7 @@
     "karma-chrome-launcher": "^0.1.12",
     "karma-coverage": "~0.3.1",
     "karma-coveralls": "^1.1.0",
-    "karma-firefox-launcher": "^0.1.6",
+    "karma-firefox-launcher": "^2.0.0",
     "karma-jasmine": "~0.3.0",
     "run-sequence": "^1.1.4"
   },