Bump spatie/laravel-data from 4.17.0 to 4.18.0 in /backend

Bumps [spatie/laravel-data](https://github.com/spatie/laravel-data) from 4.17.0 to 4.18.0.
- [Release notes](https://github.com/spatie/laravel-data/releases)
- [Changelog](https://github.com/spatie/laravel-data/blob/main/CHANGELOG.md)
- [Commits](spatie/laravel-data@4.17.0...4.18.0)

---
updated-dependencies:
- dependency-name: spatie/laravel-data
  dependency-version: 4.18.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]