Bump moment in /grr/server/grr_response_server/gui/static

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

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

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