core: bump freezegun from 1.2.2 to 1.5.1

Bumps [freezegun](https://github.com/spulec/freezegun) from 1.2.2 to 1.5.1.
- [Release notes](https://github.com/spulec/freezegun/releases)
- [Changelog](https://github.com/spulec/freezegun/blob/master/CHANGELOG)
- [Commits](spulec/freezegun@1.2.2...1.5.1)

---
updated-dependencies:
- dependency-name: freezegun
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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