chore(package): update karma-webpack to version 2.0.4

Author: greenkeeper[bot]

package.json

@@ -40,7 +40,7 @@
     "karma-remap-coverage": "0.1.4",
     "karma-sauce-launcher": "1.1.0",
     "karma-sourcemap-loader": "0.3.7",
-    "karma-webpack": "2.0.3",
+    "karma-webpack": "2.0.4",
     "mocha": "3.4.2",
     "phantomjs-prebuilt": "2.1.14",
     "semver": "5.3.0",