build(deps-dev): bump nyc from 13.3.0 to 15.1.0

Bumps [nyc](https://github.com/istanbuljs/nyc) from 13.3.0 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@v13.3.0...v15.1.0)

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

package.json

@@ -40,7 +40,7 @@
     "jest": "^26.0.1",
     "koa-livereload": "^0.2.0",
     "lint-staged": "^10.2.10",
-    "nyc": "^13.0.0",
+    "nyc": "^15.1.0",
     "supervisor": "^0.12.0"
   },
   "dependencies": {