chore(package): update jest to version 22.0.5

Closes #10

Author: greenkeeper[bot]

package.json

@@ -27,7 +27,7 @@
     "babel-preset-react": "^6.24.1",
     "babel-preset-stage-0": "^6.24.1",
     "codeclimate-test-reporter": "^0.5.0",
-    "jest": "^21.0.0",
+    "jest": "^22.0.5",
     "koa": "^2.3.0",
     "react": "^15.6.1",
     "react-dom": "^15.6.1",