Update dependency nyc to v18

Author: renovate[bot]

package.json

@@ -192,7 +192,7 @@
     "mkdirp": "^0.5.1",
     "mocha": "^6.1.4",
     "mock-require": "^3.0.3",
-    "nyc": "^14.1.1",
+    "nyc": "^18.0.0",
     "parcel-bundler": "^1.12.3",
     "prettier": "2.6.0",
     "rxjs": "^6.5.2",