chore(package): update karma to version 3.1.3

Closes #29

Author: greenkeeper[bot]

package.json

@@ -35,7 +35,7 @@
     "codelyzer": "^4.0.1",
     "jasmine-core": "~3.2.0",
     "jasmine-spec-reporter": "~4.2.1",
-    "karma": "~3.0.0",
+    "karma": "~3.1.3",
     "karma-chrome-launcher": "~2.2.0",
     "karma-coverage-istanbul-reporter": "^2.0.0",
     "karma-jasmine": "~1.1.0",