Bump phpoffice/phpspreadsheet from 1.28.0 to 1.29.1

Bumps [phpoffice/phpspreadsheet](https://github.com/PHPOffice/PhpSpreadsheet) from 1.28.0 to 1.29.1.
- [Release notes](https://github.com/PHPOffice/PhpSpreadsheet/releases)
- [Changelog](https://github.com/PHPOffice/PhpSpreadsheet/blob/1.29.1/CHANGELOG.md)
- [Commits](PHPOffice/PhpSpreadsheet@1.28.0...1.29.1)

---
updated-dependencies:
- dependency-name: phpoffice/phpspreadsheet
  dependency-type: direct:production
...

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