Bump phpmailer/phpmailer from 6.1.4 to 6.1.6 in /core (#2048)
Bump phpmailer/phpmailer from 6.1.4 to 6.1.6 in /core (#2048)

Bumps [phpmailer/phpmailer](https://github.com/PHPMailer/PHPMailer) from 6.1.4 to 6.1.6.
- [Release notes](https://github.com/PHPMailer/PHPMailer/releases)
- [Changelog](https://github.com/PHPMailer/PHPMailer/blob/master/changelog.md)
- [Commits](https://github.com/PHPMailer/PHPMailer/compare/v6.1.4...v6.1.6)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
luyadev/luya,luyadev/luya,luyadev/luya