chore(package): update nyc to version 13.2.0

Author: greenkeeper[bot]

package.json

@@ -68,7 +68,7 @@
     "eslint-plugin-ava": "^4.2.2",
     "fetch-mock": "^6.5.0",
     "husky": "^0.14.3",
-    "nyc": "^12.0.2",
+    "nyc": "^13.2.0",
     "rimraf": "^2.6.2",
     "sinon": "^6.1.3",
     "validate-commit-msg": "^2.14.0"