message: Nudge karma to 3.1.2
  This includes a fix for detecting the version of Chrome used to run tests.
diff: "file-loader": "^3.0.1",
  "flow-parser": "^0.57.3",
  "jest-mock": "^23.2.0",
  - "karma": "^3.0.0",
  + "karma": "^3.1.2",
  "karma-chrome-launcher": "^0.2.3",
  "karma-cli": "^1.0.1",
  "karma-junit-reporter": "^0.4.2",
  