fix(deps): update dependency yargs to v15

Author: renovate-bot

package-lock.json

@@ -49,7 +49,7 @@
     "uuid-parse": "1.1.0",
     "validator": "10.11.0",
     "web-push": "3.4.3",
-    "yargs": "14.2.2"
+    "yargs": "15.3.0"
   },
   "devDependencies": {
     "coveralls": "3.0.9",