chore(package): update ava to version 1.2.1

Closes #286

Author: greenkeeper[bot]

package.json

@@ -32,7 +32,7 @@
     "when": "^3.7.8"
   },
   "devDependencies": {
-    "ava": "^0.25.0",
+    "ava": "^1.2.1",
     "chalk": "^2.3.0",
     "coveralls": "^3.0.2",
     "husky": "^0.14.3",