build(deps-dev): bump odf.js from 2.4.8 to 2.4.21

Bumps [odf.js](https://github.com/ExaDev/odf.js) from 2.4.8 to 2.4.21.
- [Release notes](https://github.com/ExaDev/odf.js/releases)
- [Changelog](https://github.com/ExaDev/odf.js/blob/main/CHANGELOG.md)
- [Commits](ExaDev/odf.js@v2.4.8...v2.4.21)

---
updated-dependencies:
- dependency-name: odf.js
  dependency-version: 2.4.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]