Bump yargs from 15.3.1 to 15.4.1 in /app

Bumps [yargs](https://github.com/yargs/yargs) from 15.3.1 to 15.4.1.
- [Release notes](https://github.com/yargs/yargs/releases)
- [Changelog](https://github.com/yargs/yargs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/yargs/yargs/compare/v15.3.1...v15.4.1)

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

app/package.json

@@ -37,7 +37,7 @@
     "path": "0.12.7",
     "rxjs": "^6.5.5",
     "rxjs-compat": "^6.6.0",
-    "yargs": "^15.3.1",
+    "yargs": "^15.4.1",
     "zone.js": "^0.10.3"
   },
   "optionalDependencies": {