Bump flask-caching from 2.3.1 to 2.4.0

Bumps [flask-caching](https://github.com/pallets-eco/flask-caching) from 2.3.1 to 2.4.0.
- [Release notes](https://github.com/pallets-eco/flask-caching/releases)
- [Changelog](https://github.com/pallets-eco/flask-caching/blob/master/CHANGES.rst)
- [Commits](pallets-eco/flask-caching@v2.3.1...v2.4.0)

---
updated-dependencies:
- dependency-name: flask-caching
  dependency-version: 2.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]