build(deps): bump rfc4648 from 1.5.3 to 1.5.4

Bumps [rfc4648](https://github.com/swansontec/rfc4648.js) from 1.5.3 to 1.5.4.
- [Release notes](https://github.com/swansontec/rfc4648.js/releases)
- [Changelog](https://github.com/swansontec/rfc4648.js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/swansontec/rfc4648.js/commits)

---
updated-dependencies:
- dependency-name: rfc4648
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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