Bump nodemailer from 6.7.2 to 6.7.3

Bumps [nodemailer](https://github.com/nodemailer/nodemailer) from 6.7.2 to 6.7.3.
- [Release notes](https://github.com/nodemailer/nodemailer/releases)
- [Changelog](https://github.com/nodemailer/nodemailer/blob/master/CHANGELOG.md)
- [Commits](nodemailer/nodemailer@v6.7.2...v6.7.3)

---
updated-dependencies:
- dependency-name: nodemailer
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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