build(deps): bump mustache from 4.1.0 to 4.2.0 in /frontend

Bumps [mustache](https://github.com/janl/mustache.js) from 4.1.0 to 4.2.0.
- [Release notes](https://github.com/janl/mustache.js/releases)
- [Changelog](https://github.com/janl/mustache.js/blob/master/CHANGELOG.md)
- [Commits](janl/mustache.js@v4.1.0...v4.2.0)

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

Author: dependabot[bot]

frontend/package-lock.json

@@ -52,7 +52,7 @@
   },
   "dependencies": {
     "chartist": "^0.11.3",
-    "mustache": "^4.1.0",
+    "mustache": "^4.2.0",
     "normalize.css": "^8.0.1",
     "prismjs": "^1.23.0"
   }