dep: bump phpmailer/phpmailer from 6.9.3 to 6.10.0

Bumps [phpmailer/phpmailer](https://github.com/PHPMailer/PHPMailer) from 6.9.3 to 6.10.0.
- [Release notes](https://github.com/PHPMailer/PHPMailer/releases)
- [Changelog](https://github.com/PHPMailer/PHPMailer/blob/master/changelog.md)
- [Commits](PHPMailer/PHPMailer@v6.9.3...v6.10.0)

---
updated-dependencies:
- dependency-name: phpmailer/phpmailer
  dependency-version: 6.10.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]