build(deps): bump laravel/framework from 9.21.0 to 9.21.6

Bumps [laravel/framework](https://github.com/laravel/framework) from 9.21.0 to 9.21.6.
- [Release notes](https://github.com/laravel/framework/releases)
- [Changelog](https://github.com/laravel/framework/blob/9.x/CHANGELOG.md)
- [Commits](laravel/framework@v9.21.0...v9.21.6)

---
updated-dependencies:
- dependency-name: laravel/framework
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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