fix(package): update nyc to version 15.0.0

Author: greenkeeper[bot]

package.json

@@ -25,7 +25,7 @@
     "minify": "^5.0.0",
     "moment": "^2.24.0",
     "moment-timezone": "^0.5.27",
-    "nyc": "^14.1.1",
+    "nyc": "^15.0.0",
     "ora": "^4.0.2",
     "signale": "^1.4.0",
     "tslib": "^1.10.0"