Bump flat-cache from 3.1.0 to 3.1.1

Bumps [flat-cache](https://github.com/jaredwray/flat-cache) from 3.1.0 to 3.1.1.
- [Release notes](https://github.com/jaredwray/flat-cache/releases)
- [Changelog](https://github.com/jaredwray/flat-cache/blob/master/changelog.md)
- [Commits](https://github.com/jaredwray/flat-cache/commits/v3.1.1)

---
updated-dependencies:
- dependency-name: flat-cache
  dependency-type: indirect
  update-type: version-update:semver-patch
...

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