chore(package): update nyc to version 15.1.0

Closes #57

Author: greenkeeper[bot]

package.json

@@ -33,7 +33,7 @@
     "eslint-config-i-am-meticulous": "^11.0.0",
     "eslint-plugin-import": "^2.2.0",
     "markdown-it": "^8.2.2",
-    "nyc": "^13.1.0",
+    "nyc": "^15.1.0",
     "standard-version": "^4.4.0"
   },
   "scripts": {