Bump moment from 2.29.1 to 2.29.4 in /frontend

Bumps [moment](https://github.com/moment/moment) from 2.29.1 to 2.29.4.
- [Release notes](https://github.com/moment/moment/releases)
- [Changelog](https://github.com/moment/moment/blob/develop/CHANGELOG.md)
- [Commits](https://github.com/moment/moment/compare/2.29.1...2.29.4)

---
updated-dependencies:
- dependency-name: moment
  dependency-type: direct:production
...

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

frontend/package.json

@@ -73,7 +73,7 @@
     "loaders.css": "^0.1.2",
     "lodash": "^4.17.21",
     "m-react-splitters": "^1.2.0",
-    "moment": "^2.17.1",
+    "moment": "^2.29.4",
     "moment-timezone": "^0.5.35",
     "namor": "^1.1.2",
     "node-sass": "^4.13.0",