chore(package): update nyc to version 12.0.1

Author: greenkeeper[bot]

package.json

@@ -52,7 +52,7 @@
  "commitizen": "^2.9.6",
  "cz-conventional-changelog": "^2.0.0",
  "nock": "^9.0.18",
- "nyc": "^11.2.1",
+ "nyc": "^12.0.1",
  "proxyquire": "^2.0.0",
  "semantic-release": "^15.0.0",
  "sinon": "^5.0.0",