Bump django-unicorn from 0.52.0 to 0.55.0

Bumps [django-unicorn](https://github.com/sponsors/adamghill) from 0.52.0 to 0.55.0.
- [Commits](https://github.com/sponsors/adamghill/commits)

---
updated-dependencies:
- dependency-name: django-unicorn
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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