chore(deps-dev): bump nyc from 14.1.1 to 15.1.0

Bumps [nyc](https://github.com/istanbuljs/nyc) from 14.1.1 to 15.1.0.
- [Release notes](https://github.com/istanbuljs/nyc/releases)
- [Changelog](https://github.com/istanbuljs/nyc/blob/master/CHANGELOG.md)
- [Commits](istanbuljs/nyc@v14.1.1...v15.1.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -36,7 +36,7 @@
     "ava": "^2.0.0",
     "chalk": "^2.4.2",
     "coveralls": "^3.0.3",
-    "nyc": "^14.0.0",
+    "nyc": "^15.1.0",
     "standard": "^14.0.0",
     "standard-version": "^7.0.0"
   }