🤖 chore: Use c8 instead of nyc.

These changes were automatically generated by a transform whose code can be found at:
  - https://github.com/make-github-pseudonymous-again/rejuvenate/blob/a44c42967442d65fd14272682fb84a6f32feb841/src/transforms/coverage:replace-nyc-by-c8.js
Please contact the author of the transform if you believe there was an error.

Author: a-flying-potato

package.json

@@ -28,7 +28,7 @@
   ],
   "scripts": {
     "build": "babel src -d lib",
-    "cover": "nyc --reporter=lcov npm test",
+    "cover": "c8 --all --src src --reporter=lcov npm test",
     "dev": "npm run lint -- --fix && npm run cover -- -- -st --fail-fast",
     "esdoc": "esdoc",
     "lint": "true",
@@ -52,14 +52,14 @@
     "babel-plugin-transform-remove-console": "6.9.4",
     "babel-plugin-unassert": "3.0.1",
     "babel-preset-power-assert": "3.0.0",
+    "c8": "7.8.0",
     "coveralls": "3.1.0",
     "esdoc": "1.1.0",
     "esdoc-inject-script-plugin": "1.0.0",
     "esdoc-inject-style-plugin": "1.0.0",
     "esdoc-standard-plugin": "1.0.0",
     "fixpack": "4.0.0",
     "np": "7.4.0",
-    "nyc": "15.1.0",
     "power-assert": "1.6.1"
   },
   "ava": {