Update fakefs requirement from ~> 1.4.1 to ~> 1.8.0
Update fakefs requirement from ~> 1.4.1 to ~> 1.8.0

Updates the requirements on [fakefs](https://github.com/fakefs/fakefs) to permit the latest version.
- [Release notes](https://github.com/fakefs/fakefs/releases)
- [Changelog](https://github.com/fakefs/fakefs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/fakefs/fakefs/compare/v1.4.1...v1.8.0)

---
updated-dependencies:
- dependency-name: fakefs
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
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