Bump phpoffice/phpspreadsheet from 2.2.1 to 2.3.5

Bumps [phpoffice/phpspreadsheet](https://github.com/PHPOffice/PhpSpreadsheet) from 2.2.1 to 2.3.5.
- [Release notes](https://github.com/PHPOffice/PhpSpreadsheet/releases)
- [Changelog](https://github.com/PHPOffice/PhpSpreadsheet/blob/2.3.5/CHANGELOG.md)
- [Commits](PHPOffice/PhpSpreadsheet@2.2.1...2.3.5)

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

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