chore(package): update ava to version 3.5.1

Closes #44

Author: greenkeeper[bot]

package.json

@@ -29,7 +29,7 @@
   },
   "homepage": "https://uldissturms.github.io",
   "devDependencies": {
-    "ava": "^0.25.0",
+    "ava": "^3.5.1",
     "concat-stream": "^2.0.0",
     "nyc": "^12.0.1",
     "standard": "^11.0.0"