Bump i18next-fs-backend from 2.6.1 to 2.6.4

Bumps [i18next-fs-backend](https://github.com/i18next/i18next-fs-backend) from 2.6.1 to 2.6.4.
- [Changelog](https://github.com/i18next/i18next-fs-backend/blob/master/CHANGELOG.md)
- [Commits](https://github.com/i18next/i18next-fs-backend/compare/v2.6.1...v2.6.4)

---
updated-dependencies:
- dependency-name: i18next-fs-backend
  dependency-version: 2.6.4
  dependency-type: direct:production
...

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