Bump tar-fs and backstopjs

Bumps [tar-fs](https://github.com/mafintosh/tar-fs) to 3.0.9 and updates ancestor dependency [backstopjs](https://github.com/garris/backstopjs). These dependencies need to be updated together.


Updates `tar-fs` from 2.0.0 to 3.0.9
- [Commits](mafintosh/tar-fs@v2.0.0...v3.0.9)

Updates `backstopjs` from 5.4.4 to 6.3.25
- [Release notes](https://github.com/garris/backstopjs/releases)
- [Changelog](https://github.com/garris/BackstopJS/blob/master/changelog.md)
- [Commits](https://github.com/garris/backstopjs/commits)

---
updated-dependencies:
- dependency-name: tar-fs
  dependency-version: 3.0.9
  dependency-type: indirect
- dependency-name: backstopjs
  dependency-version: 6.3.25
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]